From patchwork Sat Sep 23 09:41:50 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Li, Xin3" X-Patchwork-Id: 13396659 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 20C66CE7A98 for ; Sat, 23 Sep 2023 10:12:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231629AbjIWKMP (ORCPT ); Sat, 23 Sep 2023 06:12:15 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58998 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231390AbjIWKLv (ORCPT ); Sat, 23 Sep 2023 06:11:51 -0400 Received: from mgamail.intel.com (mgamail.intel.com [134.134.136.100]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id F40911A6; Sat, 23 Sep 2023 03:11:44 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1695463905; x=1726999905; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=yFOHuHE47yU8Pv3f7vyK1KueQKaw2/ZJmrjuiwmDzLE=; b=IWnaelHWYToj5baMKtpTQf5PGC4D4ZkLwsJuf4tIlpR4E2dRfo2PUUgK egi3BREtFGAyWH9jlzI4T43jwfpSkka/BU1osR/pcNLe6+T2OiBJFwVKb nOGvGX4tRNdnvDC333dBFaKZIYExqD9nNmzGutw8LfDt+6qpZqJv6JqVM v22xOdDh+y/rSszfoEnzEjTYX9+IBBj6d6nd8wbvu1I99k98dNOODwsaS 9G53qj4YmgGkNaAdMaBkPs/fx1PahXV7g7KiyOrf1Q7js6CvIS7KJU6/0 3z8Y9x3DzTl+NkfvSlJl2qcAc8gVDWmvZX0KKycxQp3Y774y0Gx0BCcvS Q==; X-IronPort-AV: E=McAfee;i="6600,9927,10841"; a="447492252" X-IronPort-AV: E=Sophos;i="6.03,171,1694761200"; d="scan'208";a="447492252" Received: from fmsmga008.fm.intel.com ([10.253.24.58]) by orsmga105.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 23 Sep 2023 03:11:43 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10841"; a="813388151" X-IronPort-AV: E=Sophos;i="6.03,171,1694761200"; d="scan'208";a="813388151" Received: from unknown (HELO fred..) ([172.25.112.68]) by fmsmga008.fm.intel.com with ESMTP; 23 Sep 2023 03:11:43 -0700 From: Xin Li To: linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-edac@vger.kernel.org, linux-hyperv@vger.kernel.org, kvm@vger.kernel.org, xen-devel@lists.xenproject.org Cc: tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com, luto@kernel.org, pbonzini@redhat.com, seanjc@google.com, peterz@infradead.org, jgross@suse.com, ravi.v.shankar@intel.com, mhiramat@kernel.org, andrew.cooper3@citrix.com, jiangshanlai@gmail.com, nik.borisov@suse.com Subject: [PATCH v11 15/37] x86/ptrace: Cleanup the definition of the pt_regs structure Date: Sat, 23 Sep 2023 02:41:50 -0700 Message-Id: <20230923094212.26520-16-xin3.li@intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20230923094212.26520-1-xin3.li@intel.com> References: <20230923094212.26520-1-xin3.li@intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-edac@vger.kernel.org struct pt_regs is hard to read because the member or section related comments are not aligned with the members. The 'cs' and 'ss' members of pt_regs are type of 'unsigned long' while in reality they are only 16-bit wide. This works so far as the remaining space is unused, but FRED will use the remaining bits for other purposes. To prepare for FRED: - Cleanup the formatting - Convert 'cs' and 'ss' to u16 and embed them into an union with a u64 - Fixup the related printk() format strings Signed-off-by: H. Peter Anvin (Intel) Tested-by: Shan Kang Signed-off-by: Thomas Gleixner Signed-off-by: Xin Li --- arch/x86/entry/vsyscall/vsyscall_64.c | 2 +- arch/x86/include/asm/ptrace.h | 44 +++++++++++++++++++-------- arch/x86/kernel/process_64.c | 2 +- 3 files changed, 33 insertions(+), 15 deletions(-) diff --git a/arch/x86/entry/vsyscall/vsyscall_64.c b/arch/x86/entry/vsyscall/vsyscall_64.c index e0ca8120aea8..a3c0df11d0e6 100644 --- a/arch/x86/entry/vsyscall/vsyscall_64.c +++ b/arch/x86/entry/vsyscall/vsyscall_64.c @@ -76,7 +76,7 @@ static void warn_bad_vsyscall(const char *level, struct pt_regs *regs, if (!show_unhandled_signals) return; - printk_ratelimited("%s%s[%d] %s ip:%lx cs:%lx sp:%lx ax:%lx si:%lx di:%lx\n", + printk_ratelimited("%s%s[%d] %s ip:%lx cs:%x sp:%lx ax:%lx si:%lx di:%lx\n", level, current->comm, task_pid_nr(current), message, regs->ip, regs->cs, regs->sp, regs->ax, regs->si, regs->di); diff --git a/arch/x86/include/asm/ptrace.h b/arch/x86/include/asm/ptrace.h index f4db78b09c8f..f08ea073edd6 100644 --- a/arch/x86/include/asm/ptrace.h +++ b/arch/x86/include/asm/ptrace.h @@ -57,17 +57,19 @@ struct pt_regs { #else /* __i386__ */ struct pt_regs { -/* - * C ABI says these regs are callee-preserved. They aren't saved on kernel entry - * unless syscall needs a complete, fully filled "struct pt_regs". - */ + /* + * C ABI says these regs are callee-preserved. They aren't saved on + * kernel entry unless syscall needs a complete, fully filled + * "struct pt_regs". + */ unsigned long r15; unsigned long r14; unsigned long r13; unsigned long r12; unsigned long bp; unsigned long bx; -/* These regs are callee-clobbered. Always saved on kernel entry. */ + + /* These regs are callee-clobbered. Always saved on kernel entry. */ unsigned long r11; unsigned long r10; unsigned long r9; @@ -77,18 +79,34 @@ struct pt_regs { unsigned long dx; unsigned long si; unsigned long di; -/* - * On syscall entry, this is syscall#. On CPU exception, this is error code. - * On hw interrupt, it's IRQ number: - */ + + /* + * orig_ax is used on entry for: + * - the syscall number (syscall, sysenter, int80) + * - error_code stored by the CPU on traps and exceptions + * - the interrupt number for device interrupts + */ unsigned long orig_ax; -/* Return frame for iretq */ + + /* The IRETQ return frame starts here */ unsigned long ip; - unsigned long cs; + + union { + u64 csx; // The full 64-bit data slot containing CS + u16 cs; // CS selector + }; + unsigned long flags; unsigned long sp; - unsigned long ss; -/* top of stack page */ + + union { + u64 ssx; // The full 64-bit data slot containing SS + u16 ss; // SS selector + }; + + /* + * Top of stack on IDT systems. + */ }; #endif /* !__i386__ */ diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c index 33b268747bb7..0f78b58021bb 100644 --- a/arch/x86/kernel/process_64.c +++ b/arch/x86/kernel/process_64.c @@ -117,7 +117,7 @@ void __show_regs(struct pt_regs *regs, enum show_regs_mode mode, printk("%sFS: %016lx(%04x) GS:%016lx(%04x) knlGS:%016lx\n", log_lvl, fs, fsindex, gs, gsindex, shadowgs); - printk("%sCS: %04lx DS: %04x ES: %04x CR0: %016lx\n", + printk("%sCS: %04x DS: %04x ES: %04x CR0: %016lx\n", log_lvl, regs->cs, ds, es, cr0); printk("%sCR2: %016lx CR3: %016lx CR4: %016lx\n", log_lvl, cr2, cr3, cr4);