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| author | Tony Luck <tony.luck@intel.com> | 2014-06-04 16:10:59 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2014-06-04 16:54:13 -0700 |
| commit | a70ffcac741d31a406c1d2b832ae43d658e7e1cf (patch) | |
| tree | 656f7515976b7e5647918ba80c3b2df7a45ad9d0 /mm/memory-failure.c | |
| parent | d2f3102838d90ed6ed09a6154bdb2306f7cf1548 (diff) | |
| download | lwn-a70ffcac741d31a406c1d2b832ae43d658e7e1cf.tar.gz lwn-a70ffcac741d31a406c1d2b832ae43d658e7e1cf.zip | |
mm/memory-failure.c-failure: send right signal code to correct thread
When a thread in a multi-threaded application hits a machine check because
of an uncorrectable error in memory - we want to send the SIGBUS with
si.si_code = BUS_MCEERR_AR to that thread. Currently we fail to do that
if the active thread is not the primary thread in the process.
collect_procs() just finds primary threads and this test:
if ((flags & MF_ACTION_REQUIRED) && t == current) {
will see that the thread we found isn't the current thread and so send a
si.si_code = BUS_MCEERR_AO to the primary (and nothing to the active
thread at this time).
We can fix this by checking whether "current" shares the same mm with the
process that collect_procs() said owned the page. If so, we send the
SIGBUS to current (with code BUS_MCEERR_AR).
Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Reported-by: Otto Bruggeman <otto.g.bruggeman@intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Chen Gong <gong.chen@linux.jf.intel.com>
Cc: <stable@vger.kernel.org> [3.2+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm/memory-failure.c')
| -rw-r--r-- | mm/memory-failure.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/mm/memory-failure.c b/mm/memory-failure.c index a0474680c394..89ad452182bb 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -204,9 +204,9 @@ static int kill_proc(struct task_struct *t, unsigned long addr, int trapno, #endif si.si_addr_lsb = compound_order(compound_head(page)) + PAGE_SHIFT; - if ((flags & MF_ACTION_REQUIRED) && t == current) { + if ((flags & MF_ACTION_REQUIRED) && t->mm == current->mm) { si.si_code = BUS_MCEERR_AR; - ret = force_sig_info(SIGBUS, &si, t); + ret = force_sig_info(SIGBUS, &si, current); } else { /* * Don't use force here, it's convenient if the signal |