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| author | David Hildenbrand <dahi@linux.vnet.ibm.com> | 2015-05-11 17:52:10 +0200 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2015-05-19 08:39:15 +0200 |
| commit | ce01948eb85da733558fa77c2a554144a57ab0fb (patch) | |
| tree | 4fecfe4c672e05fb36afc1813fd8dded81dee4d9 | |
| parent | sched/preempt, mm/kmap: Explicitly disable/enable preemption in kmap_atomic_* (diff) | |
| download | linux-ce01948eb85da733558fa77c2a554144a57ab0fb.tar.xz linux-ce01948eb85da733558fa77c2a554144a57ab0fb.zip | |
sched/preempt, mm/kmap, MIPS: Disable preemption in kmap_coherent() explicitly
k(un)map_coherent relies on pagefault_disable() to also disable
preemption.
Let's make this explicit, to prepare for pagefault_disable() not
touching preemption anymore.
This patch is based on a patch by Yang Shi on the -rt tree:
"k{un}map_coherent are just called when cpu_has_dc_aliases == 1 with VIPT
cache. However, actually, the most modern MIPS processors have PIPT dcache
without dcache alias issue. In such case, k{un}map_atomic will be called
with preempt enabled."
Reviewed-and-tested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: David.Laight@ACULAB.COM
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: airlied@linux.ie
Cc: akpm@linux-foundation.org
Cc: benh@kernel.crashing.org
Cc: bigeasy@linutronix.de
Cc: borntraeger@de.ibm.com
Cc: daniel.vetter@intel.com
Cc: heiko.carstens@de.ibm.com
Cc: herbert@gondor.apana.org.au
Cc: hocko@suse.cz
Cc: hughd@google.com
Cc: mst@redhat.com
Cc: paulus@samba.org
Cc: ralf@linux-mips.org
Cc: schwidefsky@de.ibm.com
Cc: yang.shi@windriver.com
Link: http://lkml.kernel.org/r/1431359540-32227-6-git-send-email-dahi@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
| -rw-r--r-- | arch/mips/mm/init.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/arch/mips/mm/init.c b/arch/mips/mm/init.c index faa5c9822ecc..198a3147dd7d 100644 --- a/arch/mips/mm/init.c +++ b/arch/mips/mm/init.c @@ -90,6 +90,7 @@ static void *__kmap_pgprot(struct page *page, unsigned long addr, pgprot_t prot) BUG_ON(Page_dcache_dirty(page)); + preempt_disable(); pagefault_disable(); idx = (addr >> PAGE_SHIFT) & (FIX_N_COLOURS - 1); idx += in_interrupt() ? FIX_N_COLOURS : 0; @@ -152,6 +153,7 @@ void kunmap_coherent(void) write_c0_entryhi(old_ctx); local_irq_restore(flags); pagefault_enable(); + preempt_enable(); } void copy_user_highpage(struct page *to, struct page *from, |