From patchwork Sat Sep 6 17:52:36 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Ga=C3=ABl_PORTAY?= X-Patchwork-Id: 4858031 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 865119F665 for ; Sat, 6 Sep 2014 17:55:57 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 5503F2012D for ; Sat, 6 Sep 2014 17:55:56 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 274F72013A for ; Sat, 6 Sep 2014 17:55:55 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1XQKB7-0005gP-Ji; Sat, 06 Sep 2014 17:53:37 +0000 Received: from mail-wi0-x22a.google.com ([2a00:1450:400c:c05::22a]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1XQKAr-0005WT-IU for linux-arm-kernel@lists.infradead.org; Sat, 06 Sep 2014 17:53:22 +0000 Received: by mail-wi0-f170.google.com with SMTP id cc10so906160wib.3 for ; Sat, 06 Sep 2014 10:52:59 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-type:content-transfer-encoding; bh=Nv9TRqaF7/ohs6xiJ6So//RK3udf2tBr8Oandb87qlE=; b=rntmCvSsHpMygn692YtBv5glDKc4fHrVQD5Hx5Vn9BB+h8NP6H5BdNxxUB/0TH7Jz9 pdcODQ6818UcgzYaPWxDK+VLnl+2MooNx+scF0+d3vhY6y7GwuAyM3sMtgssqWd+JMED CCorpfYMa5QLMRxIdK7FlNu2OnrWXeoNXYkGkZdjJpdS7pU3aK13rNd7nahoS7u3HWpN s+nmwZOSywcw0ScSgha5NRrFXxnYIzNDeTDRGOQNJ4xrGeSGePjscYoKqrAV1tdYaRpn fIyrvezVEtgrhTExXb5dU6qUhKI62XWfttN7mfPAZy/miLvZM00gtfxyPZmEiD49Vs5c Whaw== X-Received: by 10.194.84.175 with SMTP id a15mr20972046wjz.12.1410025979217; Sat, 06 Sep 2014 10:52:59 -0700 (PDT) Received: from localhost.localdomain ([78.206.137.189]) by mx.google.com with ESMTPSA id ll20sm5697978wic.14.2014.09.06.10.52.57 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Sat, 06 Sep 2014 10:52:58 -0700 (PDT) From: =?UTF-8?q?Ga=C3=ABl=20PORTAY?= To: Arnd Bergmann , Daniel Lezcano , Greg Kroah-Hartman , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-pwm@vger.kernel.org, Nicolas Ferre , Thomas Gleixner , Thierry Reding , Boris Brezillon , Alexandre Belloni , Jean-Christophe PLAGNIOL-VILLARD Subject: [PATCHv4 3/4] ARM: at91/tclib: mask interruptions at shutdown and probe Date: Sat, 6 Sep 2014 19:52:36 +0200 Message-Id: <1410025957-5952-4-git-send-email-gael.portay@gmail.com> X-Mailer: git-send-email 1.9.3 In-Reply-To: <1410025957-5952-1-git-send-email-gael.portay@gmail.com> References: <1410025957-5952-1-git-send-email-gael.portay@gmail.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20140906_105321_923654_41EB8C51 X-CRM114-Status: GOOD ( 22.89 ) X-Spam-Score: -0.8 (/) Cc: =?utf-8?q?Ga=C3=ABl=20PORTAY?= X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-3.4 required=5.0 tests=BAYES_00, DKIM_ADSP_CUSTOM_MED, DKIM_SIGNED, FREEMAIL_FROM, RCVD_IN_DNSWL_NONE, RP_MATCHES_RCVD, T_DKIM_INVALID, UNPARSEABLE_RELAY autolearn=ham version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Shutdown properly the timer counter block by masking interruptions. Otherwise, a segmentation may happen when kexec-ing a new kernel (see backtrace below). An interruption may happen before the handler is set, leading to a kernel segmentation fault. Furthermore, we make sure the interruptions are masked when the driver is initialized. This will prevent freshly kexec-ed kernel from crashing when launched from a kernel which does not properly mask interruptions at shutdown. The backtrace below happened after kexec-ing a new kernel, from a kernel that did not shut down properly leaving interruptions unmasked. Unable to handle kernel NULL pointer dereference at virtual address 00000000 pgd = c0004000 [00000000] *pgd=00000000 Internal error: Oops: 80000005 [#1] ARM Modules linked in: CPU: 0 PID: 1 Comm: swapper Not tainted 3.16.0+ #144 task: c1828aa0 ti: c182a000 task.ti: c182a000 PC is at 0x0 LR is at ch2_irq+0x28/0x30 pc : [<00000000>] lr : [] psr: 000000d3 sp : c182bd38 ip : c182bd48 fp : c182bd44 r10: c0373390 r9 : c1825b00 r8 : 60000053 r7 : 00000000 r6 : 00000000 r5 : 00000013 r4 : c036e800 r3 : 00000000 r2 : 00002004 r1 : c036e760 r0 : c036e760 Flags: nzcv IRQs off FIQs off Mode SVC_32 ISA ARM Segment kernel Control: 0005317f Table: 20004000 DAC: 00000017 Process swapper (pid: 1, stack limit = 0xc182a1c0) Stack: (0xc182bd38 to 0xc182c000) bd20: c182bd7c c182bd48 bd40: c0045430 c01db8ec 00000000 c18c6f40 c182bd74 c1825b00 c035cec4 00000000 bd60: c182be2c 60000053 c1825b34 00000000 c182bd94 c182bd80 c0045570 c0045408 bd80: 00000000 c1825b00 c182bdac c182bd98 c0047f34 c0045550 00000013 c036619c bda0: c182bdc4 c182bdb0 c0044da4 c0047e98 0000007f 00000013 c182bde4 c182bdc8 bdc0: c0009e34 c0044d8c fefff000 c0046728 60000053 ffffffff c182bdf4 c182bde8 bde0: c00086a8 c0009ddc c182be74 c182bdf8 c000cb80 c0008674 00000000 00000013 be00: 00000000 00014200 c1825b00 c036e800 00000013 c035ed98 60000053 c1825b34 be20: 00000000 c182be74 c182be20 c182be40 c0047994 c0046728 60000053 ffffffff be40: 00000013 c036e800 c182be64 c1825b00 00000013 c036e800 c035ed98 c03874bc be60: 00000004 c036e700 c182be94 c182be78 c004689c c0046398 c036e760 c18c6080 be80: 00000000 c035ed10 c182bedc c182be98 c0348b08 c004684c 0000000c c034dac8 bea0: 004c4b3f c028c338 c036e760 00000013 c014ecc8 c18e67e0 c035b9c0 c0348884 bec0: c035b9c0 c182a020 00000000 00000000 c182bf54 c182bee0 c00089fc c0348894 bee0: c00da51c c1ffcc78 c182bf0c c182bef8 c002d100 c002d09c c1ffcc78 00000000 bf00: c182bf54 c182bf10 c002d308 c0336570 c182bf3c c0334e44 00000003 00000003 bf20: 00000030 c0334b44 c0044d74 00000003 00000003 c034dac8 c0350a94 c0373440 bf40: c0373440 00000030 c182bf94 c182bf58 c0336d24 c000890c 00000003 00000003 bf60: c0336560 c182bf64 c182bf64 6e616e0d 00000000 c0272fc8 00000000 00000000 bf80: 00000000 00000000 c182bfac c182bf98 c0272fd8 c0336bd8 c182a000 00000000 bfa0: 00000000 c182bfb0 c00095d0 c0272fd8 00000000 00000000 00000000 00000000 bfc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 bfe0: 00000000 00000000 00000000 00000000 00000013 00000000 374d27cd 33cc33e4 Backtrace: [] (ch2_irq) from [] (handle_irq_event_percpu+0x38/0x148) [] (handle_irq_event_percpu) from [] (handle_irq_event+0x30/0x40) r10:00000000 r9:c1825b34 r8:60000053 r7:c182be2c r6:00000000 r5:c035cec4 r4:c1825b00 [] (handle_irq_event) from [] (handle_fasteoi_irq+0xac/0x11c) r4:c1825b00 r3:00000000 [] (handle_fasteoi_irq) from [] (generic_handle_irq+0x28/0x38) r5:c036619c r4:00000013 [] (generic_handle_irq) from [] (handle_IRQ+0x68/0x88) r4:00000013 r3:0000007f [] (handle_IRQ) from [] (at91_aic_handle_irq+0x44/0x4c) r6:ffffffff r5:60000053 r4:c0046728 r3:fefff000 [] (at91_aic_handle_irq) from [] (__irq_svc+0x40/0x4c) Exception stack(0xc182bdf8 to 0xc182be40) bde0: 00000000 00000013 be00: 00000000 00014200 c1825b00 c036e800 00000013 c035ed98 60000053 c1825b34 be20: 00000000 c182be74 c182be20 c182be40 c0047994 c0046728 60000053 ffffffff [] (__setup_irq) from [] (setup_irq+0x60/0x8c) r10:c036e700 r9:00000004 r8:c03874bc r7:c035ed98 r6:c036e800 r5:00000013 r4:c1825b00 [] (setup_irq) from [] (tcb_clksrc_init+0x284/0x31c) r6:c035ed10 r5:00000000 r4:c18c6080 r3:c036e760 [] (tcb_clksrc_init) from [] (do_one_initcall+0x100/0x1b4) r10:00000000 r9:00000000 r8:c182a020 r7:c035b9c0 r6:c0348884 r5:c035b9c0 r4:c18e67e0 [] (do_one_initcall) from [] (kernel_init_freeable+0x15c/0x224) r9:00000030 r8:c0373440 r7:c0373440 r6:c0350a94 r5:c034dac8 r4:00000003 [] (kernel_init_freeable) from [] (kernel_init+0x10/0xec) r9:00000000 r8:00000000 r7:00000000 r6:00000000 r5:c0272fc8 r4:00000000 [] (kernel_init) from [] (ret_from_fork+0x14/0x24) r4:00000000 r3:c182a000 Code: bad PC value ---[ end trace 5b30f0017e282e47 ]--- Kernel panic - not syncing: Fatal exception in interrupt Signed-off-by: Gaël PORTAY Acked-by: Boris Brezillon Acked-by: Daniel Lezcano --- drivers/misc/atmel_tclib.c | 16 ++++++++++++++++ include/linux/atmel_tc.h | 5 +++++ 2 files changed, 21 insertions(+) diff --git a/drivers/misc/atmel_tclib.c b/drivers/misc/atmel_tclib.c index d505d1e..0ca05c3 100644 --- a/drivers/misc/atmel_tclib.c +++ b/drivers/misc/atmel_tclib.c @@ -109,6 +109,7 @@ static int __init tc_probe(struct platform_device *pdev) struct clk *clk; int irq; struct resource *r; + unsigned int i; irq = platform_get_irq(pdev, 0); if (irq < 0) @@ -157,18 +158,33 @@ static int __init tc_probe(struct platform_device *pdev) if (tc->irq[2] < 0) tc->irq[2] = irq; + for (i = 0; i < 3; i++) + writel(ATMEL_TC_ALL_IRQ, tc->regs + ATMEL_TC_REG(i, IDR)); + spin_lock(&tc_list_lock); list_add_tail(&tc->node, &tc_list); spin_unlock(&tc_list_lock); + platform_set_drvdata(pdev, tc); + return 0; } +static void tc_shutdown(struct platform_device *pdev) +{ + int i; + struct atmel_tc *tc = platform_get_drvdata(pdev); + + for (i = 0; i < 3; i++) + writel(ATMEL_TC_ALL_IRQ, tc->regs + ATMEL_TC_REG(i, IDR)); +} + static struct platform_driver tc_driver = { .driver = { .name = "atmel_tcb", .of_match_table = of_match_ptr(atmel_tcb_dt_ids), }, + .shutdown = tc_shutdown, }; static int __init tc_init(void) diff --git a/include/linux/atmel_tc.h b/include/linux/atmel_tc.h index d8aa884..b87c1c7 100644 --- a/include/linux/atmel_tc.h +++ b/include/linux/atmel_tc.h @@ -260,5 +260,10 @@ extern const u8 atmel_tc_divisors[5]; #define ATMEL_TC_LDRAS (1 << 5) /* RA loading */ #define ATMEL_TC_LDRBS (1 << 6) /* RB loading */ #define ATMEL_TC_ETRGS (1 << 7) /* external trigger */ +#define ATMEL_TC_ALL_IRQ (ATMEL_TC_COVFS | ATMEL_TC_LOVRS | \ + ATMEL_TC_CPAS | ATMEL_TC_CPBS | \ + ATMEL_TC_CPCS | ATMEL_TC_LDRAS | \ + ATMEL_TC_LDRBS | ATMEL_TC_ETRGS) \ + /* all IRQs */ #endif