All of lore.kernel.org
 help / color / mirror / Atom feed
From: Borislav Petkov <bp@alien8.de>
To: X86 ML <x86@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>,
	Josh Poimboeuf <jpoimboe@redhat.com>,
	Andy Lutomirski <luto@amacapital.net>,
	LKML <linux-kernel@vger.kernel.org>
Subject: [PATCH 2/5] x86/dumpstack: Carve out Code: dumping into a function
Date: Mon, 19 Feb 2018 21:28:23 +0100	[thread overview]
Message-ID: <20180219202826.19797-3-bp@alien8.de> (raw)
In-Reply-To: <20180219202826.19797-1-bp@alien8.de>

From: Borislav Petkov <bp@suse.de>

No functionality change, carve it out into a separate function for later
changes.

Signed-off-by: Borislav Petkov <bp@suse.de>
---
 arch/x86/kernel/dumpstack.c | 57 ++++++++++++++++++++++++---------------------
 1 file changed, 30 insertions(+), 27 deletions(-)

diff --git a/arch/x86/kernel/dumpstack.c b/arch/x86/kernel/dumpstack.c
index 18fa9d74c182..954b1dd1c04a 100644
--- a/arch/x86/kernel/dumpstack.c
+++ b/arch/x86/kernel/dumpstack.c
@@ -376,10 +376,38 @@ static int __init code_bytes_setup(char *s)
 }
 __setup("code_bytes=", code_bytes_setup);
 
+static void show_opcodes(u8 *rip)
+{
+	unsigned int code_prologue = code_bytes * 43 / 64;
+	unsigned int code_len = code_bytes;
+	unsigned char c;
+	u8 *ip;
+	int i;
+
+	printk(KERN_DEFAULT "Code: ");
+
+	ip = (u8 *)rip - code_prologue;
+	if (ip < (u8 *)PAGE_OFFSET || probe_kernel_address(ip, c)) {
+		/* try starting at IP */
+		ip = (u8 *)rip;
+		code_len = code_len - code_prologue + 1;
+	}
+	for (i = 0; i < code_len; i++, ip++) {
+		if (ip < (u8 *)PAGE_OFFSET || probe_kernel_address(ip, c)) {
+			pr_cont(" Bad RIP value.");
+			break;
+		}
+		if (ip == (u8 *)rip)
+			pr_cont("<%02x> ", c);
+		else
+			pr_cont("%02x ", c);
+	}
+	pr_cont("\n");
+}
+
 void show_regs(struct pt_regs *regs)
 {
 	bool all = true;
-	int i;
 
 	show_regs_print_info(KERN_DEFAULT);
 
@@ -393,32 +421,7 @@ void show_regs(struct pt_regs *regs)
 	 * time of the fault..
 	 */
 	if (!user_mode(regs)) {
-		unsigned int code_prologue = code_bytes * 43 / 64;
-		unsigned int code_len = code_bytes;
-		unsigned char c;
-		u8 *ip;
-
 		show_trace_log_lvl(current, regs, NULL, KERN_DEFAULT);
-
-		printk(KERN_DEFAULT "Code: ");
-
-		ip = (u8 *)regs->ip - code_prologue;
-		if (ip < (u8 *)PAGE_OFFSET || probe_kernel_address(ip, c)) {
-			/* try starting at IP */
-			ip = (u8 *)regs->ip;
-			code_len = code_len - code_prologue + 1;
-		}
-		for (i = 0; i < code_len; i++, ip++) {
-			if (ip < (u8 *)PAGE_OFFSET ||
-					probe_kernel_address(ip, c)) {
-				pr_cont(" Bad RIP value.");
-				break;
-			}
-			if (ip == (u8 *)regs->ip)
-				pr_cont("<%02x> ", c);
-			else
-				pr_cont("%02x ", c);
-		}
+		show_opcodes((u8 *)regs->ip);
 	}
-	pr_cont("\n");
 }
-- 
2.13.0

  parent reply	other threads:[~2018-02-19 20:28 UTC|newest]

Thread overview: 18+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-02-19 20:28 [PATCH 0/5] x86/dumpstack: Cleanups and user opcode bytes Code: section Borislav Petkov
2018-02-19 20:28 ` [PATCH 1/5] x86/dumpstack: Unify show_regs() Borislav Petkov
2018-02-19 20:28 ` Borislav Petkov [this message]
2018-02-19 20:28 ` [PATCH 3/5] x86/dumpstack: Improve opcodes dumping in the Code: section Borislav Petkov
2018-02-19 22:02   ` Josh Poimboeuf
2018-02-19 20:28 ` [PATCH 4/5] x86/dumpstack: Add loglevel argument to show_opcodes() Borislav Petkov
2018-02-19 20:28 ` [RFC PATCH 5/5] x86/fault: Dump user opcode bytes on fatal faults Borislav Petkov
2018-02-20 19:14 ` [PATCH 0/5] x86/dumpstack: Cleanups and user opcode bytes Code: section Andy Lutomirski
2018-02-20 19:29   ` Josh Poimboeuf
2018-02-20 20:44     ` Borislav Petkov
2018-02-21  9:15       ` Ingo Molnar
2018-02-21 17:54         ` Borislav Petkov
2018-02-21 21:39           ` Linus Torvalds
2018-02-22  9:23             ` Peter Zijlstra
2018-02-22 18:42               ` Linus Torvalds
2018-02-23 15:22                 ` Josh Poimboeuf
2018-02-23 20:12                   ` Eric W. Biederman
2018-02-25 11:35             ` Borislav Petkov

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20180219202826.19797-3-bp@alien8.de \
    --to=bp@alien8.de \
    --cc=jpoimboe@redhat.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=luto@amacapital.net \
    --cc=peterz@infradead.org \
    --cc=x86@kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.