linux_dsm_epyc7002/arch/x86/mm
Prarit Bhargava b0f4c4b32c bugs, x86: Fix printk levels for panic, softlockups and stack dumps
rsyslog will display KERN_EMERG messages on a connected
terminal.  However, these messages are useless/undecipherable
for a general user.

For example, after a softlockup we get:

 Message from syslogd@intel-s3e37-04 at Jan 25 14:18:06 ...
 kernel:Stack:

 Message from syslogd@intel-s3e37-04 at Jan 25 14:18:06 ...
 kernel:Call Trace:

 Message from syslogd@intel-s3e37-04 at Jan 25 14:18:06 ...
 kernel:Code: ff ff a8 08 75 25 31 d2 48 8d 86 38 e0 ff ff 48 89
 d1 0f 01 c8 0f ae f0 48 8b 86 38 e0 ff ff a8 08 75 08 b1 01 4c 89 e0 0f 01 c9 <e8> ea 69 dd ff 4c 29 e8 48 89 c7 e8 0f bc da ff 49 89 c4 49 89

This happens because the printk levels for these messages are
incorrect. Only an informational message should be displayed on
a terminal.

I modified the printk levels for various messages in the kernel
and tested the output by using the drivers/misc/lkdtm.c kernel
modules (ie, softlockups, panics, hard lockups, etc.) and
confirmed that the console output was still the same and that
the output to the terminals was correct.

For example, in the case of a softlockup we now see the much
more informative:

 Message from syslogd@intel-s3e37-04 at Jan 25 10:18:06 ...
 BUG: soft lockup - CPU4 stuck for 60s!

instead of the above confusing messages.

AFAICT, the messages no longer have to be KERN_EMERG.  In the
most important case of a panic we set console_verbose().  As for
the other less severe cases the correct data is output to the
console and /var/log/messages.

Successfully tested by me using the drivers/misc/lkdtm.c module.

Signed-off-by: Prarit Bhargava <prarit@redhat.com>
Cc: dzickus@redhat.com
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/1327586134-11926-1-git-send-email-prarit@redhat.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-01-26 21:28:45 +01:00
..
kmemcheck x86: Swap save_stack_trace_regs parameters 2011-06-14 22:48:51 -04:00
amdtopology.c x86, NUMA: Enable CONFIG_AMD_NUMA on 32bit too 2011-05-02 17:24:48 +02:00
dump_pagetables.c x86, mm: Create symbolic index into address_markers array 2010-07-20 16:56:19 -07:00
extable.c x86-64: Set siginfo and context on vsyscall emulation faults 2011-12-05 12:17:27 +01:00
fault.c bugs, x86: Fix printk levels for panic, softlockups and stack dumps 2012-01-26 21:28:45 +01:00
gup.c thp: add compound tail page _mapcount when mapped 2011-12-09 07:50:28 -08:00
highmem_32.c x86/paravirt: PTE updates in k(un)map_atomic need to be synchronous, regardless of lazy_mmu mode 2011-12-05 17:06:34 +01:00
hugetlbpage.c mm: Convert i_mmap_lock to a mutex 2011-05-25 08:39:18 -07:00
init_32.c memblock, x86: Replace __get_free_all_memory_range() with for_each_free_mem_range() 2011-07-14 11:47:49 -07:00
init_64.c Merge branch 'master' into x86/memblock 2011-11-28 09:46:22 -08:00
init.c Merge branch 'master' into x86/memblock 2011-11-28 09:46:22 -08:00
iomap_32.c mm: fix race in kunmap_atomic() 2010-10-27 18:03:05 -07:00
ioremap.c ioremap: Delay sanity check until after a successful mapping 2011-04-29 08:02:47 +02:00
kmmio.c x86, kmmio/mmiotrace: Fix double free of kmmio_fault_pages 2010-06-18 11:30:09 +02:00
Makefile memblock, x86: Replace memblock_x86_reserve/free_range() with generic ones 2011-07-14 11:47:53 -07:00
memtest.c memblock, x86: Replace memblock_x86_reserve/free_range() with generic ones 2011-07-14 11:47:53 -07:00
mmap.c x86-32, amd: Move va_align definition to unbreak 32-bit build 2011-08-06 11:44:57 -07:00
mmio-mod.c Merge branch 'master' into for-next 2011-09-15 15:08:18 +02:00
numa_32.c memblock, x86: Replace memblock_x86_reserve/free_range() with generic ones 2011-07-14 11:47:53 -07:00
numa_64.c memblock, x86: Make free_all_memory_core_early() explicitly free lowmem only 2011-07-14 11:47:49 -07:00
numa_emulation.c memblock, x86: Replace memblock_x86_reserve/free_range() with generic ones 2011-07-14 11:47:53 -07:00
numa_internal.h x86, NUMA: Initialize and use remap allocator from setup_node_bootmem() 2011-05-02 14:18:54 +02:00
numa.c memblock, x86: Replace memblock_x86_reserve/free_range() with generic ones 2011-07-14 11:47:53 -07:00
pageattr-test.c x86: Convert vmalloc()+memset() to vzalloc() 2011-05-28 19:53:57 +02:00
pageattr.c arch/x86/mm/pageattr.c: Quiet sparse noise; local functions should be static 2011-12-05 17:11:05 +01:00
pat_internal.h x86, pat: Fix memory leak in free_memtype 2010-05-26 11:26:04 -07:00
pat_rbtree.c rbtree: Undo augmented trees performance damage and regression 2010-07-05 14:43:50 +02:00
pat.c Merge branch 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2010-08-06 10:17:52 -07:00
pf_in.c x86: Eliminate various 'set but not used' warnings 2011-05-21 19:10:33 +02:00
pf_in.h x86 mmiotrace: move files into arch/x86/mm/. 2008-05-24 11:25:37 +02:00
pgtable_32.c x86: remove last traces of quicklist usage 2010-05-24 13:33:31 -07:00
pgtable.c x86: Flush TLB if PGD entry is changed in i386 PAE mode 2011-03-18 11:44:01 +01:00
physaddr.c x86: split __phys_addr out into separate file 2009-09-10 11:48:55 -07:00
physaddr.h x86: split __phys_addr out into separate file 2009-09-10 11:48:55 -07:00
setup_nx.c x86, cpu: Only CPU features determine NX capabilities 2010-11-10 15:43:15 -08:00
srat.c x86, acpi: Skip acpi x2apic entries if the x2apic feature is not present 2011-12-23 11:00:50 -08:00
testmmiotrace.c x86, kmmio/mmiotrace: Fix double free of kmmio_fault_pages 2010-06-18 11:30:09 +02:00
tlb.c x86, tlb, UV: Do small micro-optimization for native_flush_tlb_others() 2011-03-15 08:30:34 +01:00