The patch titled
Print utsname on Oops on all architectures
has been removed from the -mm tree. Its filename was
print-utsname-on-oops-on-all-architectures.patch
This patch was dropped because it had testing failures
------------------------------------------------------
Subject: Print utsname on Oops on all architectures
From: Joshua Wise <jwise@xxxxxxxxxx>
Background:
This patch is a follow-on to "Info dump on Oops or panic()" [1].
On some architectures, the kernel printed some information on the running
kernel, but not on all architectures. The information printed was generally
the version and build number, but it was not located in a consistant place,
and some architectures did not print it at all.
Description:
This patch uses the already-existing die_chain to print utsname information
on Oops. This patch also removes the architecture-specific utsname
printers. To avoid crashing the system further (and hence not printing the
Oops) in the case where the system is so hopelessly smashed that utsname
might be destroyed, we vsprintf the utsname data into a static buffer
first, and then just print that on crash.
Testing:
I wrote a module that does a *(int*)0 = 0; and observed that I got my
utsname data printed.
Potential impact:
This adds another line to the Oops output, causing the first few lines to
potentially scroll off the screen. This also adds a few more pointer
dereferences in the Oops path, because it adds to the die_chain notifier
chain, reducing the likelihood that the Oops will be printed if there is
very bad memory corruption.
Signed-off-by: Joshua Wise <jwise@xxxxxxxxxx>
Cc: Richard Henderson <rth@xxxxxxxxxxx>
Cc: Ivan Kokshaysky <ink@xxxxxxxxxxxxxxxxxxxx>
Cc: Russell King <rmk@xxxxxxxxxxxxxxxx>
Cc: Andi Kleen <ak@xxxxxxx>
Cc: Paul Mackerras <paulus@xxxxxxxxx>
Cc: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx>
Cc: <linux-arch@xxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
arch/alpha/kernel/process.c | 1 -
arch/i386/kernel/process.c | 7 ++-----
arch/powerpc/kernel/process.c | 5 ++---
arch/x86_64/kernel/process.c | 8 ++------
kernel/sys.c | 31 +++++++++++++++++++++++++++++++
5 files changed, 37 insertions(+), 15 deletions(-)
diff -puN arch/alpha/kernel/process.c~print-utsname-on-oops-on-all-architectures arch/alpha/kernel/process.c
--- a/arch/alpha/kernel/process.c~print-utsname-on-oops-on-all-architectures
+++ a/arch/alpha/kernel/process.c
@@ -20,7 +20,6 @@
#include <linux/slab.h>
#include <linux/user.h>
#include <linux/a.out.h>
-#include <linux/utsname.h>
#include <linux/time.h>
#include <linux/major.h>
#include <linux/stat.h>
diff -puN arch/arm/kernel/process.c~print-utsname-on-oops-on-all-architectures arch/arm/kernel/process.c
diff -puN arch/i386/kernel/process.c~print-utsname-on-oops-on-all-architectures arch/i386/kernel/process.c
--- a/arch/i386/kernel/process.c~print-utsname-on-oops-on-all-architectures
+++ a/arch/i386/kernel/process.c
@@ -27,7 +27,6 @@
#include <linux/user.h>
#include <linux/a.out.h>
#include <linux/interrupt.h>
-#include <linux/utsname.h>
#include <linux/delay.h>
#include <linux/reboot.h>
#include <linux/init.h>
@@ -309,10 +308,8 @@ void show_regs(struct pt_regs * regs)
if (user_mode_vm(regs))
printk(" ESP: %04x:%08lx",0xffff & regs->xss,regs->esp);
- printk(" EFLAGS: %08lx %s (%s %.*s)\n",
- regs->eflags, print_tainted(), init_utsname()->release,
- (int)strcspn(init_utsname()->version, " "),
- init_utsname()->version);
+ printk(" EFLAGS: %08lx %s\n",
+ regs->eflags, print_tainted());
printk("EAX: %08lx EBX: %08lx ECX: %08lx EDX: %08lx\n",
regs->eax,regs->ebx,regs->ecx,regs->edx);
printk("ESI: %08lx EDI: %08lx EBP: %08lx",
diff -puN arch/powerpc/kernel/process.c~print-utsname-on-oops-on-all-architectures arch/powerpc/kernel/process.c
--- a/arch/powerpc/kernel/process.c~print-utsname-on-oops-on-all-architectures
+++ a/arch/powerpc/kernel/process.c
@@ -32,7 +32,6 @@
#include <linux/kallsyms.h>
#include <linux/mqueue.h>
#include <linux/hardirq.h>
-#include <linux/utsname.h>
#include <asm/pgtable.h>
#include <asm/uaccess.h>
@@ -416,8 +415,8 @@ void show_regs(struct pt_regs * regs)
printk("NIP: "REG" LR: "REG" CTR: "REG"\n",
regs->nip, regs->link, regs->ctr);
- printk("REGS: %p TRAP: %04lx %s (%s)\n",
- regs, regs->trap, print_tainted(), init_utsname()->release);
+ printk("REGS: %p TRAP: %04lx %s\n",
+ regs, regs->trap, print_tainted());
printk("MSR: "REG" ", regs->msr);
printbits(regs->msr, msr_bits);
printk(" CR: %08lx XER: %08lx\n", regs->ccr, regs->xer);
diff -puN arch/x86_64/kernel/process.c~print-utsname-on-oops-on-all-architectures arch/x86_64/kernel/process.c
--- a/arch/x86_64/kernel/process.c~print-utsname-on-oops-on-all-architectures
+++ a/arch/x86_64/kernel/process.c
@@ -32,7 +32,6 @@
#include <linux/interrupt.h>
#include <linux/delay.h>
#include <linux/ptrace.h>
-#include <linux/utsname.h>
#include <linux/random.h>
#include <linux/notifier.h>
#include <linux/kprobes.h>
@@ -316,11 +315,8 @@ void __show_regs(struct pt_regs * regs)
printk("\n");
print_modules();
- printk("Pid: %d, comm: %.20s %s %s %.*s\n",
- current->pid, current->comm, print_tainted(),
- init_utsname()->release,
- (int)strcspn(init_utsname()->version, " "),
- init_utsname()->version);
+ printk("Pid: %d, comm: %.20s %s\n",
+ current->pid, current->comm, print_tainted());
printk("RIP: %04lx:[<%016lx>] ", regs->cs & 0xffff, regs->rip);
printk_address(regs->rip);
printk("RSP: %04lx:%016lx EFLAGS: %08lx\n", regs->ss, regs->rsp,
diff -puN kernel/sys.c~print-utsname-on-oops-on-all-architectures kernel/sys.c
--- a/kernel/sys.c~print-utsname-on-oops-on-all-architectures
+++ a/kernel/sys.c
@@ -27,6 +27,7 @@
#include <linux/dcookies.h>
#include <linux/suspend.h>
#include <linux/tty.h>
+#include <linux/kdebug.h>
#include <linux/signal.h>
#include <linux/cn_proc.h>
#include <linux/getcpu.h>
@@ -107,6 +108,36 @@ void (*pm_power_off_prepare)(void);
EXPORT_SYMBOL(pm_power_off_prepare);
/*
+ * Dump out UTS info on oops / panic. We pregenerate utsname_info so that
+ * we don't access utsname() if the machine is in a potentially bad state.
+ */
+
+static char *utsname_info;
+
+static int dump_utsname(struct notifier_block *self, unsigned long diecode,
+ void *p)
+{
+ printk(KERN_EMERG "%s\n", utsname_info);
+ return 0;
+}
+
+static struct notifier_block utsname_notifier = {
+ .notifier_call = dump_utsname
+};
+
+static int __init register_utsname_dump(void)
+{
+ utsname_info = kasprintf(GFP_KERNEL, "%s %s %s %s",
+ utsname()->sysname,
+ utsname()->release,
+ utsname()->version,
+ utsname()->machine);
+ register_die_notifier(&utsname_notifier);
+ return 0;
+}
+module_init(register_utsname_dump);
+
+/*
* Notifier list for kernel code which wants to be called
* at shutdown. This is used to stop any idling DMA operations
* and the like.
_
Patches currently in -mm which might be from jwise@xxxxxxxxxx are
print-utsname-on-oops-on-all-architectures.patch
-
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