From patchwork Mon Apr 19 00:55:35 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nick Kossifidis X-Patchwork-Id: 12210599 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-21.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 48D10C433B4 for ; Mon, 19 Apr 2021 00:56:45 +0000 (UTC) Received: from desiato.infradead.org (desiato.infradead.org [90.155.92.199]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id B51476101D for ; Mon, 19 Apr 2021 00:56:44 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B51476101D Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=ics.forth.gr Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=desiato.20200630; h=Sender:Content-Transfer-Encoding :Content-Type:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To:Message-Id:Date: Subject:Cc:To:From:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=tV4a9XGS+UOYkLK/J+DEG44XauKsEVDVq4t0UZBtmME=; b=rPx8A95eBs1oyfvGiDSfoTMkc 0h4TLIf1WqbEY2c0uygJTpMsyi6307O8a09kOSh3HayTnpgod/QKFeEzsARUcdEPZZDLPwv4xtKCr mlyWGctdxXDLkVGfuGGvpS4gVE4tWNLnYe5gFqYK2URgBJkkz8DM/x90f3Cs7if5a1c7i9FpbMBFr 1o1zc3XWadt6NT+m+LE4eFNE3+jsLSIZM41YT/Z59D+BMfVveAyZTo0LbY1rk/+GUi4kbtvrekYVn b40blu8MXvALw+w/AcqbOfOn3ipArOizgXKFW60O3P/vSKb7jzP4S5WVKtTFbW/t0Dm0FLoG3uscZ OR99jocDw==; Received: from localhost ([::1] helo=desiato.infradead.org) by desiato.infradead.org with esmtp (Exim 4.94 #2 (Red Hat Linux)) id 1lYID7-008qEv-9n; Mon, 19 Apr 2021 00:56:21 +0000 Received: from bombadil.infradead.org ([2607:7c80:54:e::133]) by desiato.infradead.org with esmtps (Exim 4.94 #2 (Red Hat Linux)) id 1lYID4-008qEY-JZ for linux-riscv@desiato.infradead.org; Mon, 19 Apr 2021 00:56:18 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; h=Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From:Sender :Reply-To:Content-Type:Content-ID:Content-Description; bh=ufG3ghvJ4buyCaWzU2EnehZaO+hWmO9RRHTI40RgGNs=; b=BF3Y+QuB13+S6WCiUF068iTsOj /unTwUPwVLdir51UPw5iah4lnWpUIZ/h2t7W318sqWW/WQl2bZxVzMZOJ85qoevD3zeWo4L+miPWa 1uLw+JhZJ48Gv4IOztmLA0SdjmB4I74kUzlaFXpqlPwNthqCmGsjluw4eqa43TD0rDZGqNdjmDkNr Sl2qNCsvjWLxjiEgzplp4SRra+PYFU334yKGszuITIH0wAzSaS9IyJLG+z5TqoN/jLn2Izw+9Vj4A k2M4HviKAWjj80nvNWu+yBfXO4fG4js8pfcCERchJAM20juIlISaDqj1m1mdDGviTdDa/dD9HMg2f WtuvZHHw==; Received: from mailgate.ics.forth.gr ([139.91.1.2]) by bombadil.infradead.org with esmtps (Exim 4.94 #2 (Red Hat Linux)) id 1lYICz-00Apa6-UW for linux-riscv@lists.infradead.org; Mon, 19 Apr 2021 00:56:17 +0000 Received: from av3.ics.forth.gr (av3in.ics.forth.gr [139.91.1.77]) by mailgate.ics.forth.gr (8.15.2/ICS-FORTH/V10-1.8-GATE) with ESMTP id 13J0u0S2011029 for ; Mon, 19 Apr 2021 03:56:00 +0300 (EEST) DKIM-Signature: v=1; a=rsa-sha256; d=ics.forth.gr; s=av; c=relaxed/simple; q=dns/txt; i=@ics.forth.gr; t=1618793755; x=1621385755; h=From:Sender:Reply-To:Subject:Date:Message-Id:To:Cc:MIME-Version:Content-Type: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=rEmZ8MA7Mmcm1B3W8WjBdSUosxLDHFbHVrbU4iEAoGY=; b=bkfr8VsqmbGkclM0AXFQxA6auVIAgLUl5JUWAj4wzRYSlXuZnAQvRAtZMdZEtXJ7 fYRcvDb/YJrxlut0r4nkkeCxijTCUhtxbi2K8E4xz7MGsCgZ+yBOekMhCU8sxZej 3jfjz3n6GpXpQMJBDUi4sOyWMJmMkhWWQ1X0UEaPGE/Mtp50vGc9Ap4EosGMhdSb H9fGnq+JdquTT/pPxw+epoptFmoeAk5Ja2TUvcWmwD53vC5s+ulkhVFuX+2I22SY nK29bcZqelW0YsrzEUYWvLnDoXmR44/zfdy2sqaUU3X2eJlc8akgOirK2ff4BMJi cJjt955JQQB8OLqe5Np2BQ==; X-AuditID: 8b5b014d-a70347000000209f-e3-607cd51bb1fa Received: from enigma.ics.forth.gr (enigma.ics.forth.gr [139.91.151.35]) by av3.ics.forth.gr (Symantec Messaging Gateway) with SMTP id 04.FF.08351.B15DC706; Mon, 19 Apr 2021 03:55:55 +0300 (EEST) X-ICS-AUTH-INFO: Authenticated user: mick@ics.forth.gr at ics.forth.gr From: Nick Kossifidis To: linux-riscv@lists.infradead.org, palmer@dabbelt.com Cc: paul.walmsley@sifive.com, linux-kernel@vger.kernel.org, Nick Kossifidis Subject: [PATCH v4 1/5] RISC-V: Add EM_RISCV to kexec UAPI header Date: Mon, 19 Apr 2021 03:55:35 +0300 Message-Id: <20210419005539.22729-2-mick@ics.forth.gr> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20210419005539.22729-1-mick@ics.forth.gr> References: <20210419005539.22729-1-mick@ics.forth.gr> MIME-Version: 1.0 X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFprJLMWRmVeSWpSXmKPExsXSHT1dWVf6ak2CQcMDOYvLu+awWWz73MJm 0fzuHLvFy8s9zBZts/gdWD3evHzJ4vFw0yUmj81L6j0uNV9n9/i8SS6ANYrLJiU1J7MstUjf LoEr4+b6Z2wFj9gqNn3ZyN7AeIG1i5GTQ0LARGLRgf3MXYxcHEICRxkl9n3axAaRcJO4fX8n WBGbgKbE/EsHWUBsEQFzieaZrxlBbGaBDImj+36xg9jCAo4SZ46uBouzCKhK9O27DFbPK2Am cXDtayaImfIS7cu3g83nBJozZcJnsHohoJp5/+8yQdQLSpyc+YQFYr68RPPW2cwTGPlmIUnN QpJawMi0ilEgscxYLzO5WC8tv6gkQy+9aBMjOPQYfXcw3t78Vu8QIxMH4yFGCQ5mJRHe+7U1 CUK8KYmVValF+fFFpTmpxYcYpTlYlMR5efUmxAsJpCeWpGanphakFsFkmTg4pRqYUk1jnmxq m84nJf9kzppvjq0blx1xt7ib+XSalGtJ1acGbdObV5h6jTQEts5Mn9LJeb6xUFHN8sKnxN3O Mpwdy3MjHj10Snvaekz44wqn8/pFL3g2VwswJ3Us9VuruW9Kd3SHalWtidREP/O9lyrn1X9r 8JxTez0mVFeojHvaVta0rANiR+O1Pmb8WmW2wMGcU6ru84e3B28wuSquZ9RYuPDolkfhir9m zmR+v+5gzfmJX+7PXPvUw2fZi/I/5lZaJS2i93PjJbP35pxe6rdol92s6JJZnZ8mqmQd7La+ yinzVXZF5c3bB5MfdX+ay2v5cr6A1MVgvbtLMhdcXi36/LB7b6HR9NPLvghFbzOTUWIpzkg0 1GIuKk4EANdfFgmsAgAA X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210418_175614_391184_8FC21F91 X-CRM114-Status: UNSURE ( 8.26 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org Add RISC-V to the list of supported kexec architectures, we need to add the definition early-on so that later patches can use it. EM_RISCV is 243 as per ELF psABI specification here: https://github.com/riscv/riscv-elf-psabi-doc/blob/master/riscv-elf.md Signed-off-by: Nick Kossifidis --- include/uapi/linux/kexec.h | 1 + 1 file changed, 1 insertion(+) diff --git a/include/uapi/linux/kexec.h b/include/uapi/linux/kexec.h index 05669c87a..778dc191c 100644 --- a/include/uapi/linux/kexec.h +++ b/include/uapi/linux/kexec.h @@ -42,6 +42,7 @@ #define KEXEC_ARCH_MIPS_LE (10 << 16) #define KEXEC_ARCH_MIPS ( 8 << 16) #define KEXEC_ARCH_AARCH64 (183 << 16) +#define KEXEC_ARCH_RISCV (243 << 16) /* The artificial cap on the number of segments passed to kexec_load. */ #define KEXEC_SEGMENT_MAX 16 From patchwork Mon Apr 19 00:55:36 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nick Kossifidis X-Patchwork-Id: 12210607 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 86C9CC43461 for ; Mon, 19 Apr 2021 00:56:46 +0000 (UTC) Received: from desiato.infradead.org (desiato.infradead.org [90.155.92.199]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id D0A8160C40 for ; Mon, 19 Apr 2021 00:56:45 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D0A8160C40 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=ics.forth.gr Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=desiato.20200630; h=Sender:Content-Transfer-Encoding :Content-Type:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To:Message-Id:Date: Subject:Cc:To:From:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=gcKoP+7dYi/xulMp0sXjQZ9VWXZ1aMjwHpauOhTGLts=; b=n32MzFLnSk9nWDVlxwAqiVRXd xZfZo0fxU7oTF7rHTtjejEmlvi0wHf2a4mPhY/Ig66yr47Ga+mByzHJCAYmGN2slgTHRRKKkJierZ BNsO5FwKXkrp446l2kgPKATxp6YAYD9eWpq6l2UtiiXJirI0tmI+M/4erf06C8J6A99AV2Aswt5ua eCkai2FWJDmSiYfrh4SdxC/rAeBwoxnHFSI/gTdDNivaYcAwsEOgpb0AWw5x4dydpPRHNZe8p4I2G AZWPelShrm0qAHoJqedXVKleqP6XmOluG/lrt75eA1hFn5lTYfdDlfou2kZdjrKISgJKH9qRnxqHk Quv9i7kYA==; Received: from localhost ([::1] helo=desiato.infradead.org) by desiato.infradead.org with esmtp (Exim 4.94 #2 (Red Hat Linux)) id 1lYIDH-008qG8-Hk; Mon, 19 Apr 2021 00:56:31 +0000 Received: from bombadil.infradead.org ([2607:7c80:54:e::133]) by desiato.infradead.org with esmtps (Exim 4.94 #2 (Red Hat Linux)) id 1lYID6-008qEm-Id for linux-riscv@desiato.infradead.org; Mon, 19 Apr 2021 00:56:21 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; h=Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From:Sender :Reply-To:Content-Type:Content-ID:Content-Description; bh=tabBE0ZHGoZ87CU29aKRIpdclb/IP2ti/KUP1Hkvbd4=; b=QwkO3VaRZR/hvO6R+5eCu+OQnD FrH4QxlIZwKYM/D6OZNWL96VqlSpFcBhjgOUM/N6ATSpRZo5VMBCcx5DKv4xdk7GX7DGs4gibl1pa rQC2B1BTHA0Nb0ielPT+718XC3gD7YynpkJXW/VclnnuCgFZYhJinImuX66LzVN0bLaqDI9vNUyZ+ baVSEjifUcVt36ihD2yNlbk1CX91uRw8hMyfmG6C/R4t/cFnCEcloAJVenCFlCIVBqlqt8It3h30Y /u96PnNrRTY8FP0EbM2eomZ3Jr249ypEvTifnDU+D4Csy28lRlT0/7x1gwHrnNCgteI3emN6R8rWK mYI4TcIA==; Received: from mailgate.ics.forth.gr ([139.91.1.2]) by bombadil.infradead.org with esmtps (Exim 4.94 #2 (Red Hat Linux)) id 1lYID0-00Apa5-0b for linux-riscv@lists.infradead.org; Mon, 19 Apr 2021 00:56:19 +0000 Received: from av3.ics.forth.gr (av3in.ics.forth.gr [139.91.1.77]) by mailgate.ics.forth.gr (8.15.2/ICS-FORTH/V10-1.8-GATE) with ESMTP id 13J0u09k011026 for ; Mon, 19 Apr 2021 03:56:00 +0300 (EEST) DKIM-Signature: v=1; a=rsa-sha256; d=ics.forth.gr; s=av; c=relaxed/simple; q=dns/txt; i=@ics.forth.gr; t=1618793755; x=1621385755; h=From:Sender:Reply-To:Subject:Date:Message-Id:To:Cc:MIME-Version:Content-Type: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=x1NfQeDGuzUddylrd2vfl4leKdgz1sp1myNqliXpqR8=; b=mdCd6MGlIbsK1iDKG0VRgPA0wjqRZ9LxhrY2/X+97C1ftCl9hoo0qfGu3APuA0kS h9xrtIbKY1d3G6tlsa+C4rHPQ03tGh0O8NH0rlK8G+NFoDiqdoRMSf7mZATYRb/t dcJLvhWmF0S4NvI6xTs2WDutphXlAQHxAfJdSDd6gnc4YdLcgdIN6WNvNHkErKZL 73vCxJxU/+ZCWe71jCZh6JtRf0f1FYswU2+vcGTetV/onrkcTW+QtvStIkGVLhZt x4vv6c8CbQ6q/lYnNIijIOFEdB4J1cvclkzv02UGMhmBVTFhpMXkl0ecK1xm9uAR lai2878nupkDJB77cDp7OA==; X-AuditID: 8b5b014d-a4c337000000209f-e4-607cd51b4ad9 Received: from enigma.ics.forth.gr (enigma.ics.forth.gr [139.91.151.35]) by av3.ics.forth.gr (Symantec Messaging Gateway) with SMTP id 14.FF.08351.B15DC706; Mon, 19 Apr 2021 03:55:55 +0300 (EEST) X-ICS-AUTH-INFO: Authenticated user: mick@ics.forth.gr at ics.forth.gr From: Nick Kossifidis To: linux-riscv@lists.infradead.org, palmer@dabbelt.com Cc: paul.walmsley@sifive.com, linux-kernel@vger.kernel.org, Nick Kossifidis Subject: [PATCH v4 2/5] RISC-V: Add kexec support Date: Mon, 19 Apr 2021 03:55:36 +0300 Message-Id: <20210419005539.22729-3-mick@ics.forth.gr> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20210419005539.22729-1-mick@ics.forth.gr> References: <20210419005539.22729-1-mick@ics.forth.gr> MIME-Version: 1.0 X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFprBLMWRmVeSWpSXmKPExsXSHT1dWVf6ak2CwbqnchaXd81hs9j2uYXN ovndOXaLl5d7mC3aZvE7sHq8efmSxePhpktMHpuX1Htcar7O7vF5k1wAaxSXTUpqTmZZapG+ XQJXxoePd9kL9hZX3H58k72BsSOmi5GDQ0LARGJns2oXIxeHkMBRRomnW26wdDFyAsXdJG7f 38kKYrMJaErMv3QQLC4iYC7RPPM1I4jNLJAhcXTfL3YQW1jAUGLf3QawehYBVYnlt08ygdi8 AmYS35/shJopL9G+fDsbiM0JNGfKhM9gc4SAaub9vwtVLyhxcuYTFoj58hLNW2czT2Dkm4Uk NQtJagEj0ypGgcQyY73M5GK9tPyikgy99KJNjODAY/TdwXh781u9Q4xMHIyHGCU4mJVEeO/X 1iQI8aYkVlalFuXHF5XmpBYfYpTmYFES5+XVmxAvJJCeWJKanZpakFoEk2Xi4JRqYArdmHDX 6bXA+qd5dRLN+punl6aUxToyJ9rusPiq90jsW9yF43l+n2z6vn81eW59onznocKWmGadpVs6 f2k9e3I1YmNOpMIdFcV33+aK3FBZzyQfv9lRx/Xo5K4lKSGKm6f4x7faNtQvvP1TacHuAo+k ZlVu7vJvrcdKr+VKPb614dXlhfs+T81fOm/uE99pL1x8pv2eEqAZs3jSnqbtYjx8yaVhk3g/ 7Ex3zMiYabk9bpavmPb3ebUK0zf1zPGere7Ukv7rw4Xzx2+rTmhbqHvByEphXsiNNybn8lrW Ppezffk3beIhjt+/MtSP564KdKjR8L7DcTSo60zyb95oi+dHFyi268aKVD56xODko6LEUpyR aKjFXFScCADxRaq1qwIAAA== X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210418_175614_507672_F0C3D9A0 X-CRM114-Status: GOOD ( 37.84 ) X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org This patch adds support for kexec on RISC-V. On SMP systems it depends on HOTPLUG_CPU in order to be able to bring up all harts after kexec. It also needs a recent OpenSBI version that supports the HSM extension. I tested it on riscv64 QEMU on both an smp and a non-smp system. v6: * Re-based on top of "fixes" branch * Use PAGE_SIZE and CSR_* macros where possible * Small cleanups v5: * For now depend on MMU, further changes needed for NOMMU support * Make sure stvec is aligned * Cleanup some unneeded fences * Verify control code's buffer size * Compile kexec_relocate.S with medany and norelax v4: * No functional changes, just re-based v3: * Use the new smp_shutdown_nonboot_cpus() call. * Move riscv_kexec_relocate to .rodata v2: * Pass needed parameters as arguments to riscv_kexec_relocate instead of using global variables. * Use kimage_arch to hold the fdt address of the included fdt. * Use SYM_* macros on kexec_relocate.S. * Compatibility with STRICT_KERNEL_RWX. * Compatibility with HOTPLUG_CPU for SMP * Small cleanups Signed-off-by: Nick Kossifidis --- arch/riscv/Kconfig | 15 +++ arch/riscv/include/asm/kexec.h | 49 ++++++++ arch/riscv/kernel/Makefile | 5 + arch/riscv/kernel/kexec_relocate.S | 157 ++++++++++++++++++++++++ arch/riscv/kernel/machine_kexec.c | 186 +++++++++++++++++++++++++++++ 5 files changed, 412 insertions(+) create mode 100644 arch/riscv/include/asm/kexec.h create mode 100644 arch/riscv/kernel/kexec_relocate.S create mode 100644 arch/riscv/kernel/machine_kexec.c diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index 4515a10c5..10cc19be0 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -386,6 +386,21 @@ config RISCV_SBI_V01 help This config allows kernel to use SBI v0.1 APIs. This will be deprecated in future once legacy M-mode software are no longer in use. + +config KEXEC + bool "Kexec system call" + select KEXEC_CORE + select HOTPLUG_CPU if SMP + depends on MMU + help + kexec is a system call that implements the ability to shutdown your + current kernel, and to start another kernel. It is like a reboot + but it is independent of the system firmware. And like a reboot + you can start any kernel with it, not just Linux. + + The name comes from the similarity to the exec system call. + + endmenu menu "Boot options" diff --git a/arch/riscv/include/asm/kexec.h b/arch/riscv/include/asm/kexec.h new file mode 100644 index 000000000..86e6e4922 --- /dev/null +++ b/arch/riscv/include/asm/kexec.h @@ -0,0 +1,49 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (C) 2019 FORTH-ICS/CARV + * Nick Kossifidis + */ + +#ifndef _RISCV_KEXEC_H +#define _RISCV_KEXEC_H + +#include /* For PAGE_SIZE */ + +/* Maximum physical address we can use pages from */ +#define KEXEC_SOURCE_MEMORY_LIMIT (-1UL) + +/* Maximum address we can reach in physical address mode */ +#define KEXEC_DESTINATION_MEMORY_LIMIT (-1UL) + +/* Maximum address we can use for the control code buffer */ +#define KEXEC_CONTROL_MEMORY_LIMIT (-1UL) + +/* Reserve a page for the control code buffer */ +#define KEXEC_CONTROL_PAGE_SIZE PAGE_SIZE + +#define KEXEC_ARCH KEXEC_ARCH_RISCV + +static inline void +crash_setup_regs(struct pt_regs *newregs, + struct pt_regs *oldregs) +{ + /* Dummy implementation for now */ +} + + +#define ARCH_HAS_KIMAGE_ARCH + +struct kimage_arch { + unsigned long fdt_addr; +}; + +const extern unsigned char riscv_kexec_relocate[]; +const extern unsigned int riscv_kexec_relocate_size; + +typedef void (*riscv_kexec_do_relocate)(unsigned long first_ind_entry, + unsigned long jump_addr, + unsigned long fdt_addr, + unsigned long hartid, + unsigned long va_pa_off); + +#endif diff --git a/arch/riscv/kernel/Makefile b/arch/riscv/kernel/Makefile index 647a47f54..211ef87de 100644 --- a/arch/riscv/kernel/Makefile +++ b/arch/riscv/kernel/Makefile @@ -10,6 +10,10 @@ CFLAGS_REMOVE_sbi.o = $(CC_FLAGS_FTRACE) endif CFLAGS_syscall_table.o += $(call cc-option,-Wno-override-init,) +ifdef CONFIG_KEXEC +AFLAGS_kexec_relocate.o := -mcmodel=medany -mno-relax +endif + extra-y += head.o extra-y += vmlinux.lds @@ -55,6 +59,7 @@ obj-$(CONFIG_SMP) += cpu_ops_sbi.o endif obj-$(CONFIG_HOTPLUG_CPU) += cpu-hotplug.o obj-$(CONFIG_KGDB) += kgdb.o +obj-$(CONFIG_KEXEC) += kexec_relocate.o machine_kexec.o obj-$(CONFIG_JUMP_LABEL) += jump_label.o diff --git a/arch/riscv/kernel/kexec_relocate.S b/arch/riscv/kernel/kexec_relocate.S new file mode 100644 index 000000000..84101d0a2 --- /dev/null +++ b/arch/riscv/kernel/kexec_relocate.S @@ -0,0 +1,157 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (C) 2019 FORTH-ICS/CARV + * Nick Kossifidis + */ + +#include /* For RISCV_* and REG_* macros */ +#include /* For CSR_* macros */ +#include /* For PAGE_SIZE */ +#include /* For SYM_* macros */ + +.section ".rodata" +SYM_CODE_START(riscv_kexec_relocate) + + /* + * s0: Pointer to the current entry + * s1: (const) Phys address to jump to after relocation + * s2: (const) Phys address of the FDT image + * s3: (const) The hartid of the current hart + * s4: Pointer to the destination address for the relocation + * s5: (const) Number of words per page + * s6: (const) 1, used for subtraction + * s7: (const) va_pa_offset, used when switching MMU off + * s8: (const) Physical address of the main loop + * s9: (debug) indirection page counter + * s10: (debug) entry counter + * s11: (debug) copied words counter + */ + mv s0, a0 + mv s1, a1 + mv s2, a2 + mv s3, a3 + mv s4, zero + li s5, (PAGE_SIZE / RISCV_SZPTR) + li s6, 1 + mv s7, a4 + mv s8, zero + mv s9, zero + mv s10, zero + mv s11, zero + + /* Disable / cleanup interrupts */ + csrw CSR_SIE, zero + csrw CSR_SIP, zero + + /* + * When we switch SATP.MODE to "Bare" we'll only + * play with physical addresses. However the first time + * we try to jump somewhere, the offset on the jump + * will be relative to pc which will still be on VA. To + * deal with this we set stvec to the physical address at + * the start of the loop below so that we jump there in + * any case. + */ + la s8, 1f + sub s8, s8, s7 + csrw CSR_STVEC, s8 + + /* Process entries in a loop */ +.align 2 +1: + addi s10, s10, 1 + REG_L t0, 0(s0) /* t0 = *image->entry */ + addi s0, s0, RISCV_SZPTR /* image->entry++ */ + + /* IND_DESTINATION entry ? -> save destination address */ + andi t1, t0, 0x1 + beqz t1, 2f + andi s4, t0, ~0x1 + j 1b + +2: + /* IND_INDIRECTION entry ? -> update next entry ptr (PA) */ + andi t1, t0, 0x2 + beqz t1, 2f + andi s0, t0, ~0x2 + addi s9, s9, 1 + csrw CSR_SATP, zero + jalr zero, s8, 0 + +2: + /* IND_DONE entry ? -> jump to done label */ + andi t1, t0, 0x4 + beqz t1, 2f + j 4f + +2: + /* + * IND_SOURCE entry ? -> copy page word by word to the + * destination address we got from IND_DESTINATION + */ + andi t1, t0, 0x8 + beqz t1, 1b /* Unknown entry type, ignore it */ + andi t0, t0, ~0x8 + mv t3, s5 /* i = num words per page */ +3: /* copy loop */ + REG_L t1, (t0) /* t1 = *src_ptr */ + REG_S t1, (s4) /* *dst_ptr = *src_ptr */ + addi t0, t0, RISCV_SZPTR /* stc_ptr++ */ + addi s4, s4, RISCV_SZPTR /* dst_ptr++ */ + sub t3, t3, s6 /* i-- */ + addi s11, s11, 1 /* c++ */ + beqz t3, 1b /* copy done ? */ + j 3b + +4: + /* Pass the arguments to the next kernel / Cleanup*/ + mv a0, s3 + mv a1, s2 + mv a2, s1 + + /* Cleanup */ + mv a3, zero + mv a4, zero + mv a5, zero + mv a6, zero + mv a7, zero + + mv s0, zero + mv s1, zero + mv s2, zero + mv s3, zero + mv s4, zero + mv s5, zero + mv s6, zero + mv s7, zero + mv s8, zero + mv s9, zero + mv s10, zero + mv s11, zero + + mv t0, zero + mv t1, zero + mv t2, zero + mv t3, zero + mv t4, zero + mv t5, zero + mv t6, zero + csrw CSR_SEPC, zero + csrw CSR_SCAUSE, zero + csrw CSR_SSCRATCH, zero + + /* + * Make sure the relocated code is visible + * and jump to the new kernel + */ + fence.i + + jalr zero, a2, 0 + +SYM_CODE_END(riscv_kexec_relocate) +riscv_kexec_relocate_end: + + .section ".rodata" +SYM_DATA(riscv_kexec_relocate_size, + .long riscv_kexec_relocate_end - riscv_kexec_relocate) + diff --git a/arch/riscv/kernel/machine_kexec.c b/arch/riscv/kernel/machine_kexec.c new file mode 100644 index 000000000..cd6803311 --- /dev/null +++ b/arch/riscv/kernel/machine_kexec.c @@ -0,0 +1,186 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2019 FORTH-ICS/CARV + * Nick Kossifidis + */ + +#include +#include /* For riscv_kexec_* symbol defines */ +#include /* For smp_send_stop () */ +#include /* For local_flush_icache_all() */ +#include /* For smp_wmb() */ +#include /* For PAGE_MASK */ +#include /* For fdt_check_header() */ +#include /* For set_memory_x() */ +#include /* For unreachable() */ +#include /* For cpu_down() */ + +/** + * kexec_image_info - Print received image details + */ +static void +kexec_image_info(const struct kimage *image) +{ + unsigned long i; + + pr_debug("Kexec image info:\n"); + pr_debug("\ttype: %d\n", image->type); + pr_debug("\tstart: %lx\n", image->start); + pr_debug("\thead: %lx\n", image->head); + pr_debug("\tnr_segments: %lu\n", image->nr_segments); + + for (i = 0; i < image->nr_segments; i++) { + pr_debug("\t segment[%lu]: %016lx - %016lx", i, + image->segment[i].mem, + image->segment[i].mem + image->segment[i].memsz); + pr_debug("\t\t0x%lx bytes, %lu pages\n", + (unsigned long) image->segment[i].memsz, + (unsigned long) image->segment[i].memsz / PAGE_SIZE); + } +} + +/** + * machine_kexec_prepare - Initialize kexec + * + * This function is called from do_kexec_load, when the user has + * provided us with an image to be loaded. Its goal is to validate + * the image and prepare the control code buffer as needed. + * Note that kimage_alloc_init has already been called and the + * control buffer has already been allocated. + */ +int +machine_kexec_prepare(struct kimage *image) +{ + struct kimage_arch *internal = &image->arch; + struct fdt_header fdt = {0}; + void *control_code_buffer = NULL; + unsigned int control_code_buffer_sz = 0; + int i = 0; + + kexec_image_info(image); + + if (image->type == KEXEC_TYPE_CRASH) { + pr_warn("Loading a crash kernel is unsupported for now.\n"); + return -EINVAL; + } + + /* Find the Flattened Device Tree and save its physical address */ + for (i = 0; i < image->nr_segments; i++) { + if (image->segment[i].memsz <= sizeof(fdt)) + continue; + + if (copy_from_user(&fdt, image->segment[i].buf, sizeof(fdt))) + continue; + + if (fdt_check_header(&fdt)) + continue; + + internal->fdt_addr = (unsigned long) image->segment[i].mem; + break; + } + + if (!internal->fdt_addr) { + pr_err("Device tree not included in the provided image\n"); + return -EINVAL; + } + + /* Copy the assembler code for relocation to the control page */ + control_code_buffer = page_address(image->control_code_page); + control_code_buffer_sz = page_size(image->control_code_page); + if (unlikely(riscv_kexec_relocate_size > control_code_buffer_sz)) { + pr_err("Relocation code doesn't fit within a control page\n"); + return -EINVAL; + } + memcpy(control_code_buffer, riscv_kexec_relocate, + riscv_kexec_relocate_size); + + /* Mark the control page executable */ + set_memory_x((unsigned long) control_code_buffer, 1); + + return 0; +} + + +/** + * machine_kexec_cleanup - Cleanup any leftovers from + * machine_kexec_prepare + * + * This function is called by kimage_free to handle any arch-specific + * allocations done on machine_kexec_prepare. Since we didn't do any + * allocations there, this is just an empty function. Note that the + * control buffer is freed by kimage_free. + */ +void +machine_kexec_cleanup(struct kimage *image) +{ +} + + +/* + * machine_shutdown - Prepare for a kexec reboot + * + * This function is called by kernel_kexec just before machine_kexec + * below. Its goal is to prepare the rest of the system (the other + * harts and possibly devices etc) for a kexec reboot. + */ +void machine_shutdown(void) +{ + /* + * No more interrupts on this hart + * until we are back up. + */ + local_irq_disable(); + +#if defined(CONFIG_HOTPLUG_CPU) + smp_shutdown_nonboot_cpus(smp_processor_id()); +#endif +} + +/** + * machine_crash_shutdown - Prepare to kexec after a kernel crash + * + * This function is called by crash_kexec just before machine_kexec + * below and its goal is similar to machine_shutdown, but in case of + * a kernel crash. Since we don't handle such cases yet, this function + * is empty. + */ +void +machine_crash_shutdown(struct pt_regs *regs) +{ +} + +/** + * machine_kexec - Jump to the loaded kimage + * + * This function is called by kernel_kexec which is called by the + * reboot system call when the reboot cmd is LINUX_REBOOT_CMD_KEXEC, + * or by crash_kernel which is called by the kernel's arch-specific + * trap handler in case of a kernel panic. It's the final stage of + * the kexec process where the pre-loaded kimage is ready to be + * executed. We assume at this point that all other harts are + * suspended and this hart will be the new boot hart. + */ +void __noreturn +machine_kexec(struct kimage *image) +{ + struct kimage_arch *internal = &image->arch; + unsigned long jump_addr = (unsigned long) image->start; + unsigned long first_ind_entry = (unsigned long) &image->head; + unsigned long this_hart_id = raw_smp_processor_id(); + unsigned long fdt_addr = internal->fdt_addr; + void *control_code_buffer = page_address(image->control_code_page); + riscv_kexec_do_relocate do_relocate = control_code_buffer; + + pr_notice("Will call new kernel at %08lx from hart id %lx\n", + jump_addr, this_hart_id); + pr_notice("FDT image at %08lx\n", fdt_addr); + + /* Make sure the relocation code is visible to the hart */ + local_flush_icache_all(); + + /* Jump to the relocation code */ + pr_notice("Bye...\n"); + do_relocate(first_ind_entry, jump_addr, fdt_addr, + this_hart_id, va_pa_offset); + unreachable(); +} From patchwork Mon Apr 19 00:55:37 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nick Kossifidis X-Patchwork-Id: 12210603 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4A813C43460 for ; Mon, 19 Apr 2021 00:56:45 +0000 (UTC) Received: from desiato.infradead.org (desiato.infradead.org [90.155.92.199]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id B610061057 for ; Mon, 19 Apr 2021 00:56:44 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B610061057 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=ics.forth.gr Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=desiato.20200630; h=Sender:Content-Transfer-Encoding :Content-Type:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To:Message-Id:Date: Subject:Cc:To:From:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=59SZ6LDcCCHxuyHR0+t7lNnXQsxw40aep1BMHYvjdvM=; b=JmMCfUbEzj1MKmMtqaX2ZeLcV Lg790NnKB2OwZLmWtWgEblMqMaXWCi/TF98y1QqsRW9+FhcW20MpO7lWiKMT3c64NeLXvGmtiXbkY DPxKn/YfPkcdgYT0gsu0VyLX6KnJaUvvvKMEqPayWvWh2OqNLGp2HjNYBzpV5S3SFRXwXQndZJitE hppVzQr/1Xrdj/EOAmAk3RbsnOQ2EgSRpKsOdhGGUCDtt3E6H22dlUc53WslvVm8hdnbcoZaYFjHE eyPW8de1uEwhi4/Pgq0gaGhlMLOMwWF+k+JhfDhGNoTtVjBGpk2IKBH7epwDIV0Y2jvScMqCcZ5a7 9HbaCi87A==; Received: from localhost ([::1] helo=desiato.infradead.org) by desiato.infradead.org with esmtp (Exim 4.94 #2 (Red Hat Linux)) id 1lYIDE-008qFa-1N; Mon, 19 Apr 2021 00:56:28 +0000 Received: from bombadil.infradead.org ([2607:7c80:54:e::133]) by desiato.infradead.org with esmtps (Exim 4.94 #2 (Red Hat Linux)) id 1lYID5-008qEk-Uv for linux-riscv@desiato.infradead.org; Mon, 19 Apr 2021 00:56:20 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; h=Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From:Sender :Reply-To:Content-Type:Content-ID:Content-Description; bh=AR/2cK2JaHoLZi7ygaXFY3gSOH9FT0RKNAj9Tw1W3YU=; b=5AV9n0+aTwX2zii3pYHtsgTAVw b3TXAgCuveScAtRrWaTjKCp//VjDTBjBNGhEfp9GBmqKqJiHkt4ypn746gjo3Ku5k2jiAEKRFP85X B6jHxt5XIE9axHAgFrQOsjyVWFfYhYMYjRNLG2deQg/QyIw7s1qqURKbAvT8lBAx7z08KD6pSyKm0 zkyuFyKgAkI05ms0YBuk0VyQVD24Gb0GUxu+YBomtDfXbZWaVaAKCL5fJkDy9gje6qvsXUYKvWs7j 70omF6KCdYiA7zViqyqrNNfBkuzFLAHHaukjlTLlsVZBKNko8RGTwlQ7irfJj0v63gCGMH5p0X7/Q +xteMjHw==; Received: from mailgate.ics.forth.gr ([139.91.1.2]) by bombadil.infradead.org with esmtps (Exim 4.94 #2 (Red Hat Linux)) id 1lYICz-00Apa3-W9 for linux-riscv@lists.infradead.org; Mon, 19 Apr 2021 00:56:18 +0000 Received: from av3.ics.forth.gr (av3in.ics.forth.gr [139.91.1.77]) by mailgate.ics.forth.gr (8.15.2/ICS-FORTH/V10-1.8-GATE) with ESMTP id 13J0u0c1011028 for ; Mon, 19 Apr 2021 03:56:00 +0300 (EEST) DKIM-Signature: v=1; a=rsa-sha256; d=ics.forth.gr; s=av; c=relaxed/simple; q=dns/txt; i=@ics.forth.gr; t=1618793755; x=1621385755; h=From:Sender:Reply-To:Subject:Date:Message-Id:To:Cc:MIME-Version:Content-Type: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=wxGhN8nAcE8ZMkJvgZHhZ03S5qvYuAPZ5ZFNQvpL6qQ=; b=gH0uHd9KL6uuEYeLMB+Ee55llaOyKBRjifdcpilstjoowjvOq/+l9sr1JO1kwt0X yC85a0PWn9ElA/xGLy6QZ4KMODUGAW4CPI4IsAgHT78UZhdoqCgdXx1XqWeslq2H PtHUZnRAP8g/aYIoPPhBe8Lx3FJC09f8OQB+IeFiidvRc9A1K374LmLa8fWLEj92 Cb0mU7Y0tZcdUk/3aFowMgXKCJEjIpV2xUlFR+U7QtbfGQNgR5fNRSoyvoiBEnPw qFXlzLTrM8vF3r5uQOOqPKz07mR+r+RzbyOPTXFUwJRSXPFFPwHAK9DWy1qRmYqX CiuUjWOFbQpGD2hcodhnow==; X-AuditID: 8b5b014d-a70347000000209f-e5-607cd51b5a9e Received: from enigma.ics.forth.gr (enigma.ics.forth.gr [139.91.151.35]) by av3.ics.forth.gr (Symantec Messaging Gateway) with SMTP id 24.FF.08351.B15DC706; Mon, 19 Apr 2021 03:55:55 +0300 (EEST) X-ICS-AUTH-INFO: Authenticated user: mick@ics.forth.gr at ics.forth.gr From: Nick Kossifidis To: linux-riscv@lists.infradead.org, palmer@dabbelt.com Cc: paul.walmsley@sifive.com, linux-kernel@vger.kernel.org, Nick Kossifidis Subject: [PATCH v4 3/5] RISC-V: Improve init_resources Date: Mon, 19 Apr 2021 03:55:37 +0300 Message-Id: <20210419005539.22729-4-mick@ics.forth.gr> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20210419005539.22729-1-mick@ics.forth.gr> References: <20210419005539.22729-1-mick@ics.forth.gr> MIME-Version: 1.0 X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFprJLMWRmVeSWpSXmKPExsXSHT1dWVf6ak2CwfWnchaXd81hs9j2uYXN ovndOXaLl5d7mC3aZvE7sHq8efmSxePhpktMHpuX1Htcar7O7vF5k1wAaxSXTUpqTmZZapG+ XQJXxqF1X9kLbhtWHDmzhK2BsVeji5GTQ0LAROLyrxnMXYxcHEICRxklbixvYoRIuEncvr+T FcRmE9CUmH/pIAuILSJgLtE88zVYDbNAhsTRfb/YQWxhATOJSdevsoHYLAKqEv9O3mcCsXmB 4t8PfmGBmCkv0b58O1gNJ9CcKRM+g80RAqqZ9/8uVL2gxMmZT1gg5stLNG+dzTyBkW8WktQs JKkFjEyrGAUSy4z1MpOL9dLyi0oy9NKLNjGCQ4/Rdwfj7c1v9Q4xMnEwHmKU4GBWEuG9X1uT IMSbklhZlVqUH19UmpNafIhRmoNFSZyXV29CvJBAemJJanZqakFqEUyWiYNTqoFp6q6zc400 ufyXzf/RvsH6/u+IBQJFIanSzxf80wp8zGN6IK2q+1lo29Oy1Zax6QIbDtU2WRZ1K9iFLS4z dFlZ62q+RXCPLK/+OqP4s+JVugcUl6TysicvcfG3dZH9diNz3+I2nxdWej9u/WzJsNgSxmSW v3T21bPCPYZvRR601d5xn6jbMf/5Gm9meZfCt/GH+DJ594a4nm2w94vQUdR1NvnW9sP72gmH +Utzn/hrLWZWmvbt6zM3ewmtJS3h7TM+iDMnyJWuelKVx8PDJ5vCcDj2+PKCvshpup+XdKRc 9b00ef0PgZ0mNYdjZvkkaduGzzod2Hf/yTyVThPP0syyQ6dY35cL/HB7MCl7thJLcUaioRZz UXEiAHDZpBusAgAA X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210418_175614_462473_08F4F726 X-CRM114-Status: GOOD ( 21.53 ) X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org * Kernel region is always present and we know where it is, no need to look for it inside the loop, just ignore it like the rest of the reserved regions within system's memory. * Don't call memblock_free inside the loop, if called it'll split the region of pre-allocated resources in two parts, messing things up, just re-use the previous pre-allocated resource and free any unused resources after both loops finish. Signed-off-by: Nick Kossifidis --- arch/riscv/kernel/setup.c | 91 ++++++++++++++++++++------------------- 1 file changed, 46 insertions(+), 45 deletions(-) diff --git a/arch/riscv/kernel/setup.c b/arch/riscv/kernel/setup.c index f8f15332c..030554bab 100644 --- a/arch/riscv/kernel/setup.c +++ b/arch/riscv/kernel/setup.c @@ -60,6 +60,7 @@ static DEFINE_PER_CPU(struct cpu, cpu_devices); * also add "System RAM" regions for compatibility with other * archs, and the rest of the known regions for completeness. */ +static struct resource kimage_res = { .name = "Kernel image", }; static struct resource code_res = { .name = "Kernel code", }; static struct resource data_res = { .name = "Kernel data", }; static struct resource rodata_res = { .name = "Kernel rodata", }; @@ -80,45 +81,54 @@ static int __init add_resource(struct resource *parent, return 1; } -static int __init add_kernel_resources(struct resource *res) +static int __init add_kernel_resources(void) { int ret = 0; /* * The memory region of the kernel image is continuous and - * was reserved on setup_bootmem, find it here and register - * it as a resource, then register the various segments of - * the image as child nodes + * was reserved on setup_bootmem, register it here as a + * resource, with the various segments of the image as + * child nodes. */ - if (!(res->start <= code_res.start && res->end >= data_res.end)) - return 0; - res->name = "Kernel image"; - res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY; + code_res.start = __pa_symbol(_text); + code_res.end = __pa_symbol(_etext) - 1; + code_res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY; - /* - * We removed a part of this region on setup_bootmem so - * we need to expand the resource for the bss to fit in. - */ - res->end = bss_res.end; + rodata_res.start = __pa_symbol(__start_rodata); + rodata_res.end = __pa_symbol(__end_rodata) - 1; + rodata_res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY; + + data_res.start = __pa_symbol(_data); + data_res.end = __pa_symbol(_edata) - 1; + data_res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY; + + bss_res.start = __pa_symbol(__bss_start); + bss_res.end = __pa_symbol(__bss_stop) - 1; + bss_res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY; + + kimage_res.start = code_res.start; + kimage_res.end = bss_res.end; + kimage_res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY; - ret = add_resource(&iomem_resource, res); + ret = add_resource(&iomem_resource, &kimage_res); if (ret < 0) return ret; - ret = add_resource(res, &code_res); + ret = add_resource(&kimage_res, &code_res); if (ret < 0) return ret; - ret = add_resource(res, &rodata_res); + ret = add_resource(&kimage_res, &rodata_res); if (ret < 0) return ret; - ret = add_resource(res, &data_res); + ret = add_resource(&kimage_res, &data_res); if (ret < 0) return ret; - ret = add_resource(res, &bss_res); + ret = add_resource(&kimage_res, &bss_res); return ret; } @@ -129,54 +139,42 @@ static void __init init_resources(void) struct resource *res = NULL; struct resource *mem_res = NULL; size_t mem_res_sz = 0; - int ret = 0, i = 0; - - code_res.start = __pa_symbol(_text); - code_res.end = __pa_symbol(_etext) - 1; - code_res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY; - - rodata_res.start = __pa_symbol(__start_rodata); - rodata_res.end = __pa_symbol(__end_rodata) - 1; - rodata_res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY; - - data_res.start = __pa_symbol(_data); - data_res.end = __pa_symbol(_edata) - 1; - data_res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY; - - bss_res.start = __pa_symbol(__bss_start); - bss_res.end = __pa_symbol(__bss_stop) - 1; - bss_res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY; + int num_resources = 0, res_idx = 0; + int ret = 0; /* + 1 as memblock_alloc() might increase memblock.reserved.cnt */ - mem_res_sz = (memblock.memory.cnt + memblock.reserved.cnt + 1) * sizeof(*mem_res); + num_resources = memblock.memory.cnt + memblock.reserved.cnt + 1; + res_idx = num_resources - 1; + + mem_res_sz = num_resources * sizeof(*mem_res); mem_res = memblock_alloc(mem_res_sz, SMP_CACHE_BYTES); if (!mem_res) panic("%s: Failed to allocate %zu bytes\n", __func__, mem_res_sz); + /* * Start by adding the reserved regions, if they overlap * with /memory regions, insert_resource later on will take * care of it. */ + ret = add_kernel_resources(); + if (ret < 0) + goto error; + for_each_reserved_mem_region(region) { - res = &mem_res[i++]; + res = &mem_res[res_idx--]; res->name = "Reserved"; res->flags = IORESOURCE_MEM | IORESOURCE_BUSY; res->start = __pfn_to_phys(memblock_region_reserved_base_pfn(region)); res->end = __pfn_to_phys(memblock_region_reserved_end_pfn(region)) - 1; - ret = add_kernel_resources(res); - if (ret < 0) - goto error; - else if (ret) - continue; - /* * Ignore any other reserved regions within * system memory. */ if (memblock_is_memory(res->start)) { - memblock_free((phys_addr_t) res, sizeof(struct resource)); + /* Re-use this pre-allocated resource */ + res_idx++; continue; } @@ -187,7 +185,7 @@ static void __init init_resources(void) /* Add /memory regions to the resource tree */ for_each_mem_region(region) { - res = &mem_res[i++]; + res = &mem_res[res_idx--]; if (unlikely(memblock_is_nomap(region))) { res->name = "Reserved"; @@ -205,6 +203,9 @@ static void __init init_resources(void) goto error; } + /* Clean-up any unused pre-allocated resources */ + mem_res_sz = (num_resources - res_idx + 1) * sizeof(*mem_res); + memblock_free((phys_addr_t) mem_res, mem_res_sz); return; error: From patchwork Mon Apr 19 00:55:38 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nick Kossifidis X-Patchwork-Id: 12210605 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B97F5C43470 for ; Mon, 19 Apr 2021 00:56:45 +0000 (UTC) Received: from desiato.infradead.org (desiato.infradead.org [90.155.92.199]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 08AB6610CB for ; Mon, 19 Apr 2021 00:56:45 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 08AB6610CB Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=ics.forth.gr Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=desiato.20200630; h=Sender:Content-Transfer-Encoding :Content-Type:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To:Message-Id:Date: Subject:Cc:To:From:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=N8a0/+L4BsTr8cW9O82ESuOH5GGLq72aMLW/2bwO6ZM=; b=GcEuJRBqS5Mr/TVbEoViaNAix VP70HDBNGAWLOuDfn/inr5+u0UcApvsEgYMF+02YN2T9BDF36Oi6eXZYYV94M064FQoZ6Xbs55LHH t6CBWTZfl3Fg/AEAKyICRYcbq5v6/oMjVrcSXReUxPkMdPif9l04l+IIKOxmBASoiFfDMKoJ/fsHY CmKgWaeJyH11UogNQ0q2uNVQClQuYhSF9n2nLI0ax/guK48/5qZMFVJJy2Wd29eorBSghR6+Kuq6x Fi/wnYiYE7H3PrBoRBjC8OorMFjfike5jvUToeRdQJn3ZM/lKIm7U6gUKtfWOm3iyo49Y+YfILFsN rsqFporsQ==; Received: from localhost ([::1] helo=desiato.infradead.org) by desiato.infradead.org with esmtp (Exim 4.94 #2 (Red Hat Linux)) id 1lYIDF-008qFk-4e; Mon, 19 Apr 2021 00:56:29 +0000 Received: from bombadil.infradead.org ([2607:7c80:54:e::133]) by desiato.infradead.org with esmtps (Exim 4.94 #2 (Red Hat Linux)) id 1lYID6-008qEl-D4 for linux-riscv@desiato.infradead.org; Mon, 19 Apr 2021 00:56:20 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; h=Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From:Sender :Reply-To:Content-Type:Content-ID:Content-Description; bh=80dz/kHllS5AsQq/K7QSDtALWMU29bJW7AiikoNg+30=; b=VoA5aR4JB3ec5/Cktcc/VtcLug PvWdededZybYIq/zuf+7NpyoNd1q9iHkkQ4WpzuKu914Vs5j75Dy60XMdt8BAdmrE+aNSEVlUwwfX 0kxj3C+AWy0se6WOkd+vo27FO34C89h1Oo+SviQJf7y2MZfFjiFPaZVZZGqYex7V+jkKcrmBCp56K GagyerRC4aM8DgOWoXuO61mx0551TM7xb6byVB6j2NkhsL593qa0Tke9KVBWdPTqKhKS69QVIs14N bcwLEn29Y6Q7WcwTowta7i4dxzfxwsltQD3dNSrEf/w4/E2n60jQ1vKZtln0iG3aIpvjBbzPpKM/G R/AiP2Mw==; Received: from mailgate.ics.forth.gr ([139.91.1.2]) by bombadil.infradead.org with esmtps (Exim 4.94 #2 (Red Hat Linux)) id 1lYICz-00Apa4-WB for linux-riscv@lists.infradead.org; Mon, 19 Apr 2021 00:56:19 +0000 Received: from av3.ics.forth.gr (av3in.ics.forth.gr [139.91.1.77]) by mailgate.ics.forth.gr (8.15.2/ICS-FORTH/V10-1.8-GATE) with ESMTP id 13J0u0SG011030 for ; Mon, 19 Apr 2021 03:56:00 +0300 (EEST) DKIM-Signature: v=1; a=rsa-sha256; d=ics.forth.gr; s=av; c=relaxed/simple; q=dns/txt; i=@ics.forth.gr; t=1618793755; x=1621385755; h=From:Sender:Reply-To:Subject:Date:Message-Id:To:Cc:MIME-Version:Content-Type: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=QE6GhjFDcH8+ocFLbkRzxLLv6DmSIWPrBspyuXY+FKA=; b=bKdI1/u860p9KmJdz1xP06LeizIIXfY/gqQBwUt74tVl3IB1F1tO5S2POoK8gU94 8fldnRsHfJMrkbxMXrPDAXqw/e7r8AfiDUO6ZKDXrCqTA2RWq1vn6IZLbWYHNa2I D0KkrQrM5fkvmqMfhbBGeNbygo0DzD+smGM0bvsKAJflx/MC0r6jSDE8NDBBJZ0Y 2bul2htIywmVooAYMJGigXcH290GWeZglcG1V/BmhjhE3XcutEHMOWwwcj7to4M5 aJwwEOtpuU1K06erVB4TBK+a0o4Y2HI7ZtB7Iy2yT7uHiwXWUAbat+/yoZfiFHTb Azhcp+54hCkDLuq8QlZcNA==; X-AuditID: 8b5b014d-a4c337000000209f-e6-607cd51b8d9f Received: from enigma.ics.forth.gr (enigma.ics.forth.gr [139.91.151.35]) by av3.ics.forth.gr (Symantec Messaging Gateway) with SMTP id 34.FF.08351.B15DC706; Mon, 19 Apr 2021 03:55:55 +0300 (EEST) X-ICS-AUTH-INFO: Authenticated user: mick@ics.forth.gr at ics.forth.gr From: Nick Kossifidis To: linux-riscv@lists.infradead.org, palmer@dabbelt.com Cc: paul.walmsley@sifive.com, linux-kernel@vger.kernel.org, Nick Kossifidis Subject: [PATCH v4 4/5] RISC-V: Add kdump support Date: Mon, 19 Apr 2021 03:55:38 +0300 Message-Id: <20210419005539.22729-5-mick@ics.forth.gr> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20210419005539.22729-1-mick@ics.forth.gr> References: <20210419005539.22729-1-mick@ics.forth.gr> MIME-Version: 1.0 X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFprGLMWRmVeSWpSXmKPExsXSHT1dWVf6ak2CwcnP8haXd81hs9j2uYXN ovndOXaLl5d7mC3aZvE7sHq8efmSxePhpktMHpuX1Htcar7O7vF5k1wAaxSXTUpqTmZZapG+ XQJXxuHvy5gKzhdUTF//hqmBcXF0FyMnh4SAicTUo8eZuhi5OIQEjjJKfO07wgiRcJO4fX8n K4jNJqApMf/SQRYQW0TAXKJ55muwGmaBDImj+36xdzFycAgLGEpMvaYNYrIIqEocv2YBYvIK mElMmWwAMVBeon35djYQmxNoyJQJn8GGCAGVzPt/lwnE5hUQlDg58wkLxHB5ieats5knMPLN QpKahSS1gJFpFaNAYpmxXmZysV5aflFJhl560SZGcNAx+u5gvL35rd4hRiYOxkOMEhzMSiK8 92trEoR4UxIrq1KL8uOLSnNSiw8xSnOwKInz8upNiBcSSE8sSc1OTS1ILYLJMnFwSjUwHbHY /6D+T2+H+qW3x2MVghL3y21WOvzG4/CN5NlJz2QfMtndUHL8vXf1YXNFgY0VchfT5izIt63V MPDg+ly1xf/qdzPGFXPW6lW9FTq4pvFHe+jzZV+L7RyTfrMUOYgc3WJl3MySfWduTlHJzdmz T57jWlJaYnj1pvcst3ymYOMA7qnsFiuOv/2hEVZ8dLXHI1f2bcfLmouynXUdJtcdqOGwDFfe 9tzYO6ZcVjise7liytaD3b93pnK+1qqes/N7KuOKUH+tEmnH2u9SM8RevtpS+Sk6lPuDp/Qr w81ClywEC8/Mdni36/+mV3VVmbc6X0yeV39m2szFEmFGrlMW8798ti3Q3y22enuidZ28Ektx RqKhFnNRcSIAjO0sAKkCAAA= X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210418_175614_490041_F197E673 X-CRM114-Status: GOOD ( 36.84 ) X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org This patch adds support for kdump, the kernel will reserve a region for the crash kernel and jump there on panic. In order for userspace tools (kexec-tools) to prepare the crash kernel kexec image, we also need to expose some information on /proc/iomem for the memory regions used by the kernel and for the region reserved for crash kernel. Note that on userspace the device tree is used to determine the system's memory layout so the "System RAM" on /proc/iomem is ignored. I tested this on riscv64 qemu and works as expected, you may test it by triggering a crash through /proc/sysrq_trigger: echo c > /proc/sysrq_trigger v4: * Re-base on top of "fixes" branch * Use CSR_* macros and PMD_SIZE where possible v3: * Move ELF_CORE_COPY_REGS to asm/elf.h instead of uapi/asm/elf.h * Set stvec when disabling MMU * Minor cleanups and re-base v2: * Properly populate the ioresources tree, so that it can be used later on for implementing strict /dev/mem. * Minor cleanups and re-base Signed-off-by: Nick Kossifidis --- arch/riscv/include/asm/elf.h | 6 +++ arch/riscv/include/asm/kexec.h | 19 +++++--- arch/riscv/kernel/Makefile | 2 +- arch/riscv/kernel/crash_save_regs.S | 56 +++++++++++++++++++++++ arch/riscv/kernel/kexec_relocate.S | 68 ++++++++++++++++++++++++++- arch/riscv/kernel/machine_kexec.c | 43 +++++++++-------- arch/riscv/kernel/setup.c | 11 ++++- arch/riscv/mm/init.c | 71 +++++++++++++++++++++++++++++ 8 files changed, 249 insertions(+), 27 deletions(-) create mode 100644 arch/riscv/kernel/crash_save_regs.S diff --git a/arch/riscv/include/asm/elf.h b/arch/riscv/include/asm/elf.h index 5c725e1df..f4b490cd0 100644 --- a/arch/riscv/include/asm/elf.h +++ b/arch/riscv/include/asm/elf.h @@ -81,4 +81,10 @@ extern int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp); #endif /* CONFIG_MMU */ +#define ELF_CORE_COPY_REGS(dest, regs) \ +do { \ + *(struct user_regs_struct *)&(dest) = \ + *(struct user_regs_struct *)regs; \ +} while (0); + #endif /* _ASM_RISCV_ELF_H */ diff --git a/arch/riscv/include/asm/kexec.h b/arch/riscv/include/asm/kexec.h index 86e6e4922..1e9541019 100644 --- a/arch/riscv/include/asm/kexec.h +++ b/arch/riscv/include/asm/kexec.h @@ -23,11 +23,16 @@ #define KEXEC_ARCH KEXEC_ARCH_RISCV +extern void riscv_crash_save_regs(struct pt_regs *newregs); + static inline void crash_setup_regs(struct pt_regs *newregs, struct pt_regs *oldregs) { - /* Dummy implementation for now */ + if (oldregs) + memcpy(newregs, oldregs, sizeof(struct pt_regs)); + else + riscv_crash_save_regs(newregs); } @@ -40,10 +45,12 @@ struct kimage_arch { const extern unsigned char riscv_kexec_relocate[]; const extern unsigned int riscv_kexec_relocate_size; -typedef void (*riscv_kexec_do_relocate)(unsigned long first_ind_entry, - unsigned long jump_addr, - unsigned long fdt_addr, - unsigned long hartid, - unsigned long va_pa_off); +typedef void (*riscv_kexec_method)(unsigned long first_ind_entry, + unsigned long jump_addr, + unsigned long fdt_addr, + unsigned long hartid, + unsigned long va_pa_off); + +extern riscv_kexec_method riscv_kexec_norelocate; #endif diff --git a/arch/riscv/kernel/Makefile b/arch/riscv/kernel/Makefile index 211ef87de..41a1469b2 100644 --- a/arch/riscv/kernel/Makefile +++ b/arch/riscv/kernel/Makefile @@ -59,7 +59,7 @@ obj-$(CONFIG_SMP) += cpu_ops_sbi.o endif obj-$(CONFIG_HOTPLUG_CPU) += cpu-hotplug.o obj-$(CONFIG_KGDB) += kgdb.o -obj-$(CONFIG_KEXEC) += kexec_relocate.o machine_kexec.o +obj-$(CONFIG_KEXEC) += kexec_relocate.o crash_save_regs.o machine_kexec.o obj-$(CONFIG_JUMP_LABEL) += jump_label.o diff --git a/arch/riscv/kernel/crash_save_regs.S b/arch/riscv/kernel/crash_save_regs.S new file mode 100644 index 000000000..7832fb763 --- /dev/null +++ b/arch/riscv/kernel/crash_save_regs.S @@ -0,0 +1,56 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (C) 2020 FORTH-ICS/CARV + * Nick Kossifidis + */ + +#include /* For RISCV_* and REG_* macros */ +#include /* For CSR_* macros */ +#include /* For offsets on pt_regs */ +#include /* For SYM_* macros */ + +.section ".text" +SYM_CODE_START(riscv_crash_save_regs) + REG_S ra, PT_RA(a0) /* x1 */ + REG_S sp, PT_SP(a0) /* x2 */ + REG_S gp, PT_GP(a0) /* x3 */ + REG_S tp, PT_TP(a0) /* x4 */ + REG_S t0, PT_T0(a0) /* x5 */ + REG_S t1, PT_T1(a0) /* x6 */ + REG_S t2, PT_T2(a0) /* x7 */ + REG_S s0, PT_S0(a0) /* x8/fp */ + REG_S s1, PT_S1(a0) /* x9 */ + REG_S a0, PT_A0(a0) /* x10 */ + REG_S a1, PT_A1(a0) /* x11 */ + REG_S a2, PT_A2(a0) /* x12 */ + REG_S a3, PT_A3(a0) /* x13 */ + REG_S a4, PT_A4(a0) /* x14 */ + REG_S a5, PT_A5(a0) /* x15 */ + REG_S a6, PT_A6(a0) /* x16 */ + REG_S a7, PT_A7(a0) /* x17 */ + REG_S s2, PT_S2(a0) /* x18 */ + REG_S s3, PT_S3(a0) /* x19 */ + REG_S s4, PT_S4(a0) /* x20 */ + REG_S s5, PT_S5(a0) /* x21 */ + REG_S s6, PT_S6(a0) /* x22 */ + REG_S s7, PT_S7(a0) /* x23 */ + REG_S s8, PT_S8(a0) /* x24 */ + REG_S s9, PT_S9(a0) /* x25 */ + REG_S s10, PT_S10(a0) /* x26 */ + REG_S s11, PT_S11(a0) /* x27 */ + REG_S t3, PT_T3(a0) /* x28 */ + REG_S t4, PT_T4(a0) /* x29 */ + REG_S t5, PT_T5(a0) /* x30 */ + REG_S t6, PT_T6(a0) /* x31 */ + + csrr t1, CSR_STATUS + csrr t2, CSR_EPC + csrr t3, CSR_TVAL + csrr t4, CSR_CAUSE + + REG_S t1, PT_STATUS(a0) + REG_S t2, PT_EPC(a0) + REG_S t3, PT_BADADDR(a0) + REG_S t4, PT_CAUSE(a0) + ret +SYM_CODE_END(riscv_crash_save_regs) diff --git a/arch/riscv/kernel/kexec_relocate.S b/arch/riscv/kernel/kexec_relocate.S index 84101d0a2..88c3beabe 100644 --- a/arch/riscv/kernel/kexec_relocate.S +++ b/arch/riscv/kernel/kexec_relocate.S @@ -151,7 +151,73 @@ SYM_CODE_START(riscv_kexec_relocate) SYM_CODE_END(riscv_kexec_relocate) riscv_kexec_relocate_end: - .section ".rodata" + +/* Used for jumping to crashkernel */ +.section ".text" +SYM_CODE_START(riscv_kexec_norelocate) + /* + * s0: (const) Phys address to jump to + * s1: (const) Phys address of the FDT image + * s2: (const) The hartid of the current hart + * s3: (const) va_pa_offset, used when switching MMU off + */ + mv s0, a1 + mv s1, a2 + mv s2, a3 + mv s3, a4 + + /* Disable / cleanup interrupts */ + csrw CSR_SIE, zero + csrw CSR_SIP, zero + + /* Switch to physical addressing */ + la s4, 1f + sub s4, s4, s3 + csrw CSR_STVEC, s4 + csrw CSR_SATP, zero + +.align 2 +1: + /* Pass the arguments to the next kernel / Cleanup*/ + mv a0, s2 + mv a1, s1 + mv a2, s0 + + /* Cleanup */ + mv a3, zero + mv a4, zero + mv a5, zero + mv a6, zero + mv a7, zero + + mv s0, zero + mv s1, zero + mv s2, zero + mv s3, zero + mv s4, zero + mv s5, zero + mv s6, zero + mv s7, zero + mv s8, zero + mv s9, zero + mv s10, zero + mv s11, zero + + mv t0, zero + mv t1, zero + mv t2, zero + mv t3, zero + mv t4, zero + mv t5, zero + mv t6, zero + csrw CSR_SEPC, zero + csrw CSR_SCAUSE, zero + csrw CSR_SSCRATCH, zero + + jalr zero, a2, 0 +SYM_CODE_END(riscv_kexec_norelocate) + +.section ".rodata" SYM_DATA(riscv_kexec_relocate_size, .long riscv_kexec_relocate_end - riscv_kexec_relocate) diff --git a/arch/riscv/kernel/machine_kexec.c b/arch/riscv/kernel/machine_kexec.c index cd6803311..51e2671a3 100644 --- a/arch/riscv/kernel/machine_kexec.c +++ b/arch/riscv/kernel/machine_kexec.c @@ -59,11 +59,6 @@ machine_kexec_prepare(struct kimage *image) kexec_image_info(image); - if (image->type == KEXEC_TYPE_CRASH) { - pr_warn("Loading a crash kernel is unsupported for now.\n"); - return -EINVAL; - } - /* Find the Flattened Device Tree and save its physical address */ for (i = 0; i < image->nr_segments; i++) { if (image->segment[i].memsz <= sizeof(fdt)) @@ -85,17 +80,21 @@ machine_kexec_prepare(struct kimage *image) } /* Copy the assembler code for relocation to the control page */ - control_code_buffer = page_address(image->control_code_page); - control_code_buffer_sz = page_size(image->control_code_page); - if (unlikely(riscv_kexec_relocate_size > control_code_buffer_sz)) { - pr_err("Relocation code doesn't fit within a control page\n"); - return -EINVAL; - } - memcpy(control_code_buffer, riscv_kexec_relocate, - riscv_kexec_relocate_size); + if (image->type != KEXEC_TYPE_CRASH) { + control_code_buffer = page_address(image->control_code_page); + control_code_buffer_sz = page_size(image->control_code_page); - /* Mark the control page executable */ - set_memory_x((unsigned long) control_code_buffer, 1); + if (unlikely(riscv_kexec_relocate_size > control_code_buffer_sz)) { + pr_err("Relocation code doesn't fit within a control page\n"); + return -EINVAL; + } + + memcpy(control_code_buffer, riscv_kexec_relocate, + riscv_kexec_relocate_size); + + /* Mark the control page executable */ + set_memory_x((unsigned long) control_code_buffer, 1); + } return 0; } @@ -147,6 +146,9 @@ void machine_shutdown(void) void machine_crash_shutdown(struct pt_regs *regs) { + crash_save_cpu(regs, smp_processor_id()); + machine_shutdown(); + pr_info("Starting crashdump kernel...\n"); } /** @@ -169,7 +171,12 @@ machine_kexec(struct kimage *image) unsigned long this_hart_id = raw_smp_processor_id(); unsigned long fdt_addr = internal->fdt_addr; void *control_code_buffer = page_address(image->control_code_page); - riscv_kexec_do_relocate do_relocate = control_code_buffer; + riscv_kexec_method kexec_method = NULL; + + if (image->type != KEXEC_TYPE_CRASH) + kexec_method = control_code_buffer; + else + kexec_method = (riscv_kexec_method) &riscv_kexec_norelocate; pr_notice("Will call new kernel at %08lx from hart id %lx\n", jump_addr, this_hart_id); @@ -180,7 +187,7 @@ machine_kexec(struct kimage *image) /* Jump to the relocation code */ pr_notice("Bye...\n"); - do_relocate(first_ind_entry, jump_addr, fdt_addr, - this_hart_id, va_pa_offset); + kexec_method(first_ind_entry, jump_addr, fdt_addr, + this_hart_id, va_pa_offset); unreachable(); } diff --git a/arch/riscv/kernel/setup.c b/arch/riscv/kernel/setup.c index 030554bab..31866dce9 100644 --- a/arch/riscv/kernel/setup.c +++ b/arch/riscv/kernel/setup.c @@ -20,6 +20,7 @@ #include #include #include +#include #include #include @@ -160,6 +161,14 @@ static void __init init_resources(void) if (ret < 0) goto error; +#ifdef CONFIG_KEXEC_CORE + if (crashk_res.start != crashk_res.end) { + ret = add_resource(&iomem_resource, &crashk_res); + if (ret < 0) + goto error; + } +#endif + for_each_reserved_mem_region(region) { res = &mem_res[res_idx--]; @@ -252,7 +261,6 @@ void __init setup_arch(char **cmdline_p) efi_init(); setup_bootmem(); paging_init(); - init_resources(); #if IS_ENABLED(CONFIG_BUILTIN_DTB) unflatten_and_copy_device_tree(); #else @@ -263,6 +271,7 @@ void __init setup_arch(char **cmdline_p) #endif misc_mem_init(); + init_resources(); sbi_init(); if (IS_ENABLED(CONFIG_STRICT_KERNEL_RWX)) diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c index 067583ab1..8b2b85a57 100644 --- a/arch/riscv/mm/init.c +++ b/arch/riscv/mm/init.c @@ -2,6 +2,8 @@ /* * Copyright (C) 2012 Regents of the University of California * Copyright (C) 2019 Western Digital Corporation or its affiliates. + * Copyright (C) 2020 FORTH-ICS/CARV + * Nick Kossifidis */ #include @@ -14,6 +16,7 @@ #include #include #include +#include #include #include @@ -585,6 +588,71 @@ void mark_rodata_ro(void) } #endif +#ifdef CONFIG_KEXEC_CORE +/* + * reserve_crashkernel() - reserves memory for crash kernel + * + * This function reserves memory area given in "crashkernel=" kernel command + * line parameter. The memory reserved is used by dump capture kernel when + * primary kernel is crashing. + */ +static void __init reserve_crashkernel(void) +{ + unsigned long long crash_base = 0; + unsigned long long crash_size = 0; + unsigned long search_start = memblock_start_of_DRAM(); + unsigned long search_end = memblock_end_of_DRAM(); + + int ret = 0; + + ret = parse_crashkernel(boot_command_line, memblock_phys_mem_size(), + &crash_size, &crash_base); + if (ret || !crash_size) + return; + + crash_size = PAGE_ALIGN(crash_size); + + if (crash_base == 0) { + /* + * Current riscv boot protocol requires 2MB alignment for + * RV64 and 4MB alignment for RV32 (hugepage size) + */ + crash_base = memblock_find_in_range(search_start, search_end, + crash_size, PMD_SIZE); + + if (crash_base == 0) { + pr_warn("crashkernel: couldn't allocate %lldKB\n", + crash_size >> 10); + return; + } + } else { + /* User specifies base address explicitly. */ + if (!memblock_is_region_memory(crash_base, crash_size)) { + pr_warn("crashkernel: requested region is not memory\n"); + return; + } + + if (memblock_is_region_reserved(crash_base, crash_size)) { + pr_warn("crashkernel: requested region is reserved\n"); + return; + } + + + if (!IS_ALIGNED(crash_base, PMD_SIZE)) { + pr_warn("crashkernel: requested region is misaligned\n"); + return; + } + } + memblock_reserve(crash_base, crash_size); + + pr_info("crashkernel: reserved 0x%016llx - 0x%016llx (%lld MB)\n", + crash_base, crash_base + crash_size, crash_size >> 20); + + crashk_res.start = crash_base; + crashk_res.end = crash_base + crash_size - 1; +} +#endif /* CONFIG_KEXEC_CORE */ + void __init paging_init(void) { setup_vm_final(); @@ -596,6 +664,9 @@ void __init misc_mem_init(void) arch_numa_init(); sparse_init(); zone_sizes_init(); +#ifdef CONFIG_KEXEC_CORE + reserve_crashkernel(); +#endif memblock_dump_all(); } From patchwork Mon Apr 19 00:55:39 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nick Kossifidis X-Patchwork-Id: 12210601 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4A8C2C43462 for ; Mon, 19 Apr 2021 00:56:45 +0000 (UTC) Received: from desiato.infradead.org (desiato.infradead.org [90.155.92.199]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id B511960C40 for ; Mon, 19 Apr 2021 00:56:44 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B511960C40 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=ics.forth.gr Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=desiato.20200630; h=Sender:Content-Transfer-Encoding :Content-Type:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To:Message-Id:Date: Subject:Cc:To:From:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=yHn6v7KleycpYeK8kA9tsqISMxVKhxkQAYAFs2lIF54=; b=FC2eSZRAmzgiJfwGGQcH9cd1s fP54BFy/Zjnf/v+Ygm056jD/WWd3EtytAM8O5KmGVgFTTT6fpay6WyqeODlbL1lb6SxVbk+QBhIkl CZReHqU0ZJhbFPp9F0yjWO6Oc8hiHocQMRaoMhAPCqX0rQw33gtyAMse7m0EoAbk2aIl2XD9V2ju2 0FCjvRHC0zkuqJ/kOYSre8I9g7YhkpOD8hBSvyVOeinfCN0kqw7GqSnwjAYJr9AQRpyo2VgSDMekk ILrQoDWFuU2dqlShAw07Ji7Ln6AFLmmD+F9XVBMfZ/bxsx41hhkOoQuQtZtPGYbSW14vSP3+4YElq xDNAWDJhA==; Received: from localhost ([::1] helo=desiato.infradead.org) by desiato.infradead.org with esmtp (Exim 4.94 #2 (Red Hat Linux)) id 1lYIDC-008qFO-PS; Mon, 19 Apr 2021 00:56:26 +0000 Received: from bombadil.infradead.org ([2607:7c80:54:e::133]) by desiato.infradead.org with esmtps (Exim 4.94 #2 (Red Hat Linux)) id 1lYID5-008qEi-QC for linux-riscv@desiato.infradead.org; Mon, 19 Apr 2021 00:56:20 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; h=Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From:Sender :Reply-To:Content-Type:Content-ID:Content-Description; bh=s0fHOfEK58w2A4SX8iRAu1pd/h+dliwHMluOgZ/NTgo=; b=Fw7WcsxBUulE9BFsUaHxgObmqP zXMVcNgKZW1HpdV+bIclaq+OvxoA7WJqgpQt050YajozO9k+bYJCA/BO9GS2bwEyVNr67ebW5zMoN UVwEQLllqxCF9C9Be4u5SIgSESPlu+/e4VXc3w78623oGYsqAel+/DBNftP7WHj5cR/5bdtIepPwm L1PzqfZxvXlzB/Dm0fz5TsYwW2rle5Dppedtp4RWsxW4V/QU9c+1i4eRS19ze3uAVXACq1tuycqR+ ufVeoscl+b3yfsytH7HphAUYhIfp1ycauhxWmFPSoyW8UH0h7yc72zCIs4uETvs9mtpkrFFLyouHs 7iYX15vA==; Received: from mailgate.ics.forth.gr ([139.91.1.2]) by bombadil.infradead.org with esmtps (Exim 4.94 #2 (Red Hat Linux)) id 1lYICz-00Apa7-VS for linux-riscv@lists.infradead.org; Mon, 19 Apr 2021 00:56:18 +0000 Received: from av3.ics.forth.gr (av3in.ics.forth.gr [139.91.1.77]) by mailgate.ics.forth.gr (8.15.2/ICS-FORTH/V10-1.8-GATE) with ESMTP id 13J0u0S6011029 for ; Mon, 19 Apr 2021 03:56:00 +0300 (EEST) DKIM-Signature: v=1; a=rsa-sha256; d=ics.forth.gr; s=av; c=relaxed/simple; q=dns/txt; i=@ics.forth.gr; t=1618793755; x=1621385755; h=From:Sender:Reply-To:Subject:Date:Message-Id:To:Cc:MIME-Version:Content-Type: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=Opd8Luf/TIYWDEE/fDRX+p0He/q818rZmFtOAhbaGrk=; b=O2e5dLci+HQ52+wfFsesogpfVZJvoGfEFYFzcow72PsIRbe2KhWjqo7xCXuX1qZv fGOwfQoa2nsk7Md5pokmVlh9r1IFp/U9AEJXMra3C5SaZRSSTnUpLjvUSouH9AVs ndHKSzb30uxssX8yJRNE6TfPgwiqz669O98uCTz0k3emh66YcAPKFMQxPuY4FVxQ 1cKqz2KDPSSpzjcs8NDVrQG2/FdUVmLMUe0uIdWYXcdVSWQb3qNOHetEPCrJUPXa ocgxxK67HKXdCTy1Dcpfgfn9ScWvQzFY8s3SyA+FhOLFNaulHfCjktn9HVJBiL+y zZTY6ttItj1aT1tZWl7n4g==; X-AuditID: 8b5b014d-a70347000000209f-e7-607cd51bc184 Received: from enigma.ics.forth.gr (enigma.ics.forth.gr [139.91.151.35]) by av3.ics.forth.gr (Symantec Messaging Gateway) with SMTP id 35.FF.08351.B15DC706; Mon, 19 Apr 2021 03:55:55 +0300 (EEST) X-ICS-AUTH-INFO: Authenticated user: mick@ics.forth.gr at ics.forth.gr From: Nick Kossifidis To: linux-riscv@lists.infradead.org, palmer@dabbelt.com Cc: paul.walmsley@sifive.com, linux-kernel@vger.kernel.org, Nick Kossifidis Subject: [PATCH v4 5/5] RISC-V: Add crash kernel support Date: Mon, 19 Apr 2021 03:55:39 +0300 Message-Id: <20210419005539.22729-6-mick@ics.forth.gr> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20210419005539.22729-1-mick@ics.forth.gr> References: <20210419005539.22729-1-mick@ics.forth.gr> MIME-Version: 1.0 X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFprBLMWRmVeSWpSXmKPExsXSHT1dWVf6ak2CwZe1KhaXd81hs9j2uYXN ovndOXaLl5d7mC3aZvE7sHq8efmSxePhpktMHpuX1Htcar7O7vF5k1wAaxSXTUpqTmZZapG+ XQJXxqcrB1gK9ppUzN30j7mB8a5WFyMnh4SAiUT7ofOMXYxcHEICRxklOvq7GCESbhK37+9k BbHZBDQl5l86yAJiiwiYSzTPfA1WwyyQIXF03y92EFtYwEJiZtNUsDiLgKrEvTOLgWwODl4B M4mPj+MgRspLtC/fzgZicwKNmTLhM1i5EFDJvP93mUBsXgFBiZMzn7BAjJeXaN46m3kCI98s JKlZSFILGJlWMQoklhnrZSYX66XlF5Vk6KUXbWIEBx6j7w7G25vf6h1iZOJgPMQowcGsJMJ7 v7YmQYg3JbGyKrUoP76oNCe1+BCjNAeLkjgvr96EeCGB9MSS1OzU1ILUIpgsEwenVAPTbua9 WsITt506OvNmZYN6Js9e26LfXjemzOKwnN3/tff2KqZV0gJTu2S5Z67eb8wxNXPfk3m50i3M 8n8vVT77mbcuzO/Mg0Ndltv2horpGc7pPdQ1Qf1b36m9l6e8NN/TuHxLnNCPjDsskvHr2DWm bp8b9lxVLZ0r/tDdpkNMn6tMebVLov3WrHv+bnGCqb9XJV+eeX26f/nqaUFzWGOKK79JBfFf 0r3rsPZ+n2OInIZk0Jnsrz0rBTjXXXxxusitQvno/gcXH2foif1ee/aG7dH+mm9V95TWxFww XH3y4lPR1wWz4nWfVM+enLjH+8viF0GyPN8cyt6ujtotPL+atVuYjVH/YNbDL0/3xkheVmIp zkg01GIuKk4EAEQhQEOrAgAA X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210418_175614_434392_0FE4FDE8 X-CRM114-Status: GOOD ( 29.90 ) X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org This patch allows Linux to act as a crash kernel for use with kdump. Userspace will let the crash kernel know about the memory region it can use through linux,usable-memory property on the /memory node (overriding its reg property), and about the memory region where the elf core header of the previous kernel is saved, through a reserved-memory node with a compatible string of "linux,elfcorehdr". This approach is the least invasive and re-uses functionality already present. I tested this on riscv64 qemu and it works as expected, you may test it by retrieving the dmesg of the previous kernel through /proc/vmcore, using the vmcore-dmesg utility from kexec-tools. v4: * Rebase on top of "fixes" branch v3: * Rebase v2: * Use linux,usable-memory on /memory instead of a new binding * Use a reserved-memory node for ELF core header Signed-off-by: Nick Kossifidis --- arch/riscv/Kconfig | 10 ++++++++ arch/riscv/kernel/Makefile | 1 + arch/riscv/kernel/crash_dump.c | 46 ++++++++++++++++++++++++++++++++++ arch/riscv/kernel/setup.c | 12 +++++++++ arch/riscv/mm/init.c | 33 ++++++++++++++++++++++++ 5 files changed, 102 insertions(+) create mode 100644 arch/riscv/kernel/crash_dump.c diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index 10cc19be0..39aa18ef4 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -400,6 +400,16 @@ config KEXEC The name comes from the similarity to the exec system call. +config CRASH_DUMP + bool "Build kdump crash kernel" + help + Generate crash dump after being started by kexec. This should + be normally only set in special crash dump kernels which are + loaded in the main kernel with kexec-tools into a specially + reserved region and then later executed after a crash by + kdump/kexec. + + For more details see Documentation/admin-guide/kdump/kdump.rst endmenu diff --git a/arch/riscv/kernel/Makefile b/arch/riscv/kernel/Makefile index 41a1469b2..d3081e4d9 100644 --- a/arch/riscv/kernel/Makefile +++ b/arch/riscv/kernel/Makefile @@ -60,6 +60,7 @@ endif obj-$(CONFIG_HOTPLUG_CPU) += cpu-hotplug.o obj-$(CONFIG_KGDB) += kgdb.o obj-$(CONFIG_KEXEC) += kexec_relocate.o crash_save_regs.o machine_kexec.o +obj-$(CONFIG_CRASH_DUMP) += crash_dump.o obj-$(CONFIG_JUMP_LABEL) += jump_label.o diff --git a/arch/riscv/kernel/crash_dump.c b/arch/riscv/kernel/crash_dump.c new file mode 100644 index 000000000..86cc0ada5 --- /dev/null +++ b/arch/riscv/kernel/crash_dump.c @@ -0,0 +1,46 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * This code comes from arch/arm64/kernel/crash_dump.c + * Created by: AKASHI Takahiro + * Copyright (C) 2017 Linaro Limited + */ + +#include +#include + +/** + * copy_oldmem_page() - copy one page from old kernel memory + * @pfn: page frame number to be copied + * @buf: buffer where the copied page is placed + * @csize: number of bytes to copy + * @offset: offset in bytes into the page + * @userbuf: if set, @buf is in a user address space + * + * This function copies one page from old kernel memory into buffer pointed by + * @buf. If @buf is in userspace, set @userbuf to %1. Returns number of bytes + * copied or negative error in case of failure. + */ +ssize_t copy_oldmem_page(unsigned long pfn, char *buf, + size_t csize, unsigned long offset, + int userbuf) +{ + void *vaddr; + + if (!csize) + return 0; + + vaddr = memremap(__pfn_to_phys(pfn), PAGE_SIZE, MEMREMAP_WB); + if (!vaddr) + return -ENOMEM; + + if (userbuf) { + if (copy_to_user((char __user *)buf, vaddr + offset, csize)) { + memunmap(vaddr); + return -EFAULT; + } + } else + memcpy(buf, vaddr + offset, csize); + + memunmap(vaddr); + return csize; +} diff --git a/arch/riscv/kernel/setup.c b/arch/riscv/kernel/setup.c index 31866dce9..ff398a3d8 100644 --- a/arch/riscv/kernel/setup.c +++ b/arch/riscv/kernel/setup.c @@ -66,6 +66,9 @@ static struct resource code_res = { .name = "Kernel code", }; static struct resource data_res = { .name = "Kernel data", }; static struct resource rodata_res = { .name = "Kernel rodata", }; static struct resource bss_res = { .name = "Kernel bss", }; +#ifdef CONFIG_CRASH_DUMP +static struct resource elfcorehdr_res = { .name = "ELF Core hdr", }; +#endif static int __init add_resource(struct resource *parent, struct resource *res) @@ -169,6 +172,15 @@ static void __init init_resources(void) } #endif +#ifdef CONFIG_CRASH_DUMP + if (elfcorehdr_size > 0) { + elfcorehdr_res.start = elfcorehdr_addr; + elfcorehdr_res.end = elfcorehdr_addr + elfcorehdr_size - 1; + elfcorehdr_res.flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY; + add_resource(&iomem_resource, &elfcorehdr_res); + } +#endif + for_each_reserved_mem_region(region) { res = &mem_res[res_idx--]; diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c index 8b2b85a57..9c048fccb 100644 --- a/arch/riscv/mm/init.c +++ b/arch/riscv/mm/init.c @@ -13,6 +13,7 @@ #include #include #include +#include #include #include #include @@ -605,6 +606,18 @@ static void __init reserve_crashkernel(void) int ret = 0; + /* + * Don't reserve a region for a crash kernel on a crash kernel + * since it doesn't make much sense and we have limited memory + * resources. + */ +#ifdef CONFIG_CRASH_DUMP + if (is_kdump_kernel()) { + pr_info("crashkernel: ignoring reservation request\n"); + return; + } +#endif + ret = parse_crashkernel(boot_command_line, memblock_phys_mem_size(), &crash_size, &crash_base); if (ret || !crash_size) @@ -653,6 +666,26 @@ static void __init reserve_crashkernel(void) } #endif /* CONFIG_KEXEC_CORE */ +#ifdef CONFIG_CRASH_DUMP +/* + * We keep track of the ELF core header of the crashed + * kernel with a reserved-memory region with compatible + * string "linux,elfcorehdr". Here we register a callback + * to populate elfcorehdr_addr/size when this region is + * present. Note that this region will be marked as + * reserved once we call early_init_fdt_scan_reserved_mem() + * later on. + */ +static int elfcore_hdr_setup(struct reserved_mem *rmem) +{ + elfcorehdr_addr = rmem->base; + elfcorehdr_size = rmem->size; + return 0; +} + +RESERVEDMEM_OF_DECLARE(elfcorehdr, "linux,elfcorehdr", elfcore_hdr_setup); +#endif + void __init paging_init(void) { setup_vm_final();