From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 5621582D98; Mon, 6 Jan 2025 15:28:52 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736177332; cv=none; b=h4cLz+vEvXTkF3iOZjcrZc8DY3EWcHkCNhX2QeDgTmvDA/fuhW8T417qsqcEdWpHaHp27gZS0rMVYCih6a76Aao0Qmw5Q6XZibKZsNwnD35qi2tUr64TJf1BpGVV76+q8PHKjsd9LcGzd+WT1vdrvLDaYxITkKbPk3j4SeV5uT4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736177332; c=relaxed/simple; bh=zu2Y6cMTVkjrBvh7s36DCD4TXXiSD+/ttA23ZVoaCok=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=XZ/p54keWHHHlwVnbKuvi4OrUfzcepQl03quwczz4TqXy1OsZrknth82oAe3XPHpa2hN1v509mR4MzJBi//A+CsG/zew8Xb57/n6EltB3k31y/V4JXoSklKpU0TlRleJ6nlDCc26j+Vn6TDVmwQyXzFMsR9pqG1GVi4kFMzjjd4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=FeZXEl4t; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="FeZXEl4t" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B0089C4CED2; Mon, 6 Jan 2025 15:28:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1736177332; bh=zu2Y6cMTVkjrBvh7s36DCD4TXXiSD+/ttA23ZVoaCok=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=FeZXEl4tdItpTQKA12jcI2l2/sk0xTyrqnn8C//YLjA2EHLrHNl3U42u2oWL1EM6M cSFd9JtkXVTx215Atpqz9zMWvRM78u1TOKRFYtqMvG4uQrVrDqwC81r3teXgv4qIXQ V1W1shLFhd6AASHbXzkCzAUVdTIc+fhAoMdM7V1U= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Thomas Gleixner , Xin Li , "Borislav Petkov (AMD)" , Shan Kang , Sasha Levin , "H. Peter Anvin (Intel)" Subject: [PATCH 6.6 097/222] x86/ptrace: Cleanup the definition of the pt_regs structure Date: Mon, 6 Jan 2025 16:15:01 +0100 Message-ID: <20250106151154.268669635@linuxfoundation.org> X-Mailer: git-send-email 2.47.1 In-Reply-To: <20250106151150.585603565@linuxfoundation.org> References: <20250106151150.585603565@linuxfoundation.org> User-Agent: quilt/0.68 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Xin Li [ Upstream commit ee63291aa8287cb7ded767d340155fe8681fc075 ] 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 Suggested-by: Thomas Gleixner Originally-by: H. Peter Anvin (Intel) Signed-off-by: Xin Li Signed-off-by: Thomas Gleixner Signed-off-by: Borislav Petkov (AMD) Tested-by: Shan Kang Link: https://lore.kernel.org/r/20231205105030.8698-14-xin3.li@intel.com Stable-dep-of: dc81e556f2a0 ("x86/fred: Clear WFE in missing-ENDBRANCH #CPs") Signed-off-by: Sasha Levin --- arch/x86/entry/vsyscall/vsyscall_64.c | 2 +- arch/x86/include/asm/ptrace.h | 48 +++++++++++++++++++-------- arch/x86/kernel/process_64.c | 2 +- 3 files changed, 37 insertions(+), 15 deletions(-) diff --git a/arch/x86/entry/vsyscall/vsyscall_64.c b/arch/x86/entry/vsyscall/vsyscall_64.c index 1245000a8792..2fb7d53cf333 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..b268cd2a2d01 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 +79,38 @@ 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 { + /* The full 64-bit data slot containing CS */ + u64 csx; + /* CS selector */ + u16 cs; + }; + unsigned long flags; unsigned long sp; - unsigned long ss; -/* top of stack page */ + + union { + /* The full 64-bit data slot containing SS */ + u64 ssx; + /* SS selector */ + u16 ss; + }; + + /* + * 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 d595ef7c1de0..dd19a4db741a 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); -- 2.39.5