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| author | Pavan Naregundi <pavan@linux.vnet.ibm.com> | 2010-06-29 15:05:28 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2010-06-29 15:29:31 -0700 |
| commit | e05bd3367bd3d88715b53766f95bb3a8ec7ab59e (patch) | |
| tree | db9f13cd687c39bf873ff5dbed28bbd142fc6940 /kernel/kexec.c | |
| parent | 482ce512c543f3b30ab881702fa997e71252e604 (diff) | |
| download | linux-e05bd3367bd3d88715b53766f95bb3a8ec7ab59e.tar.gz linux-e05bd3367bd3d88715b53766f95bb3a8ec7ab59e.tar.bz2 linux-e05bd3367bd3d88715b53766f95bb3a8ec7ab59e.zip | |
kexec: fix Oops in crash_shrink_memory()
When crashkernel is not enabled, "echo 0 > /sys/kernel/kexec_crash_size"
OOPSes the kernel in crash_shrink_memory. This happens when
crash_shrink_memory tries to release the 'crashk_res' resource which are
not reserved. Also value of "/sys/kernel/kexec_crash_size" shows as 1,
which should be 0.
This patch fixes the OOPS in crash_shrink_memory and shows
"/sys/kernel/kexec_crash_size" as 0 when crash kernel memory is not
reserved.
Signed-off-by: Pavan Naregundi <pavan@linux.vnet.ibm.com>
Reviewed-by: WANG Cong <xiyou.wangcong@gmail.com>
Cc: Simon Horman <horms@verge.net.au>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'kernel/kexec.c')
| -rw-r--r-- | kernel/kexec.c | 7 |
1 files changed, 4 insertions, 3 deletions
diff --git a/kernel/kexec.c b/kernel/kexec.c index 474a84715eac..131b1703936f 100644 --- a/kernel/kexec.c +++ b/kernel/kexec.c @@ -1089,9 +1089,10 @@ void crash_kexec(struct pt_regs *regs) size_t crash_get_memory_size(void) { - size_t size; + size_t size = 0; mutex_lock(&kexec_mutex); - size = crashk_res.end - crashk_res.start + 1; + if (crashk_res.end != crashk_res.start) + size = crashk_res.end - crashk_res.start + 1; mutex_unlock(&kexec_mutex); return size; } @@ -1134,7 +1135,7 @@ int crash_shrink_memory(unsigned long new_size) free_reserved_phys_range(end, crashk_res.end); - if (start == end) + if ((start == end) && (crashk_res.parent != NULL)) release_resource(&crashk_res); crashk_res.end = end - 1; |