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| author | Mingkai Hu <Mingkai.hu@freescale.com> | 2012-04-16 04:05:06 +0200 |
|---|---|---|
| committer | Kumar Gala <galak@kernel.crashing.org> | 2012-04-19 21:55:56 +0200 |
| commit | e0a5a6c38190a5016bcb0f1267324a19b846a35a (patch) | |
| tree | 7b8c6f20b23303f6d6cca4d32010fab70bc73b7b | |
| parent | powerpc/mpic_msgr: fix compile error when SMP disabled (diff) | |
| download | linux-e0a5a6c38190a5016bcb0f1267324a19b846a35a.tar.xz linux-e0a5a6c38190a5016bcb0f1267324a19b846a35a.zip | |
powerpc/mpic_msgr: add lock for MPIC message global variable
Also fix issue of accessing invalid msgr pointer issue. The local
msgr pointer in fucntion mpic_msgr_get will be accessed before
getting a valid address which will cause kernel crash.
Signed-off-by: Mingkai Hu <Mingkai.hu@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
| -rw-r--r-- | arch/powerpc/sysdev/mpic_msgr.c | 10 |
1 files changed, 5 insertions, 5 deletions
diff --git a/arch/powerpc/sysdev/mpic_msgr.c b/arch/powerpc/sysdev/mpic_msgr.c index 6e7fa386e76a..dc1cfe380070 100644 --- a/arch/powerpc/sysdev/mpic_msgr.c +++ b/arch/powerpc/sysdev/mpic_msgr.c @@ -27,6 +27,7 @@ static struct mpic_msgr **mpic_msgrs; static unsigned int mpic_msgr_count; +static DEFINE_RAW_SPINLOCK(msgrs_lock); static inline void _mpic_msgr_mer_write(struct mpic_msgr *msgr, u32 value) { @@ -56,12 +57,11 @@ struct mpic_msgr *mpic_msgr_get(unsigned int reg_num) if (reg_num >= mpic_msgr_count) return ERR_PTR(-ENODEV); - raw_spin_lock_irqsave(&msgr->lock, flags); - if (mpic_msgrs[reg_num]->in_use == MSGR_FREE) { - msgr = mpic_msgrs[reg_num]; + raw_spin_lock_irqsave(&msgrs_lock, flags); + msgr = mpic_msgrs[reg_num]; + if (msgr->in_use == MSGR_FREE) msgr->in_use = MSGR_INUSE; - } - raw_spin_unlock_irqrestore(&msgr->lock, flags); + raw_spin_unlock_irqrestore(&msgrs_lock, flags); return msgr; } |