diff options
| author | FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> | 2008-09-13 01:16:45 +0900 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2008-10-08 20:22:58 -0700 |
| commit | e568b3605f6f6ad1e9cbe37231cf5b578ff16d4b (patch) | |
| tree | 6a88f01f46ccc4d7dd8918597f3f56cba73b5378 | |
| parent | 2e8e9ac3bd989d4a654b7750e04a6ce5f60b0dc5 (diff) | |
sg: disable interrupts inside sg_copy_buffer
This is the backport of the upstream commit 50bed2e2862a8f3a4f7d683d0d27292e71ef18b9
The callers of sg_copy_buffer must disable interrupts before calling
it (since it uses kmap_atomic). Some callers use it on
interrupt-disabled code but some need to take the trouble to disable
interrupts just for this. No wonder they forget about it and we hit a
bug like:
http://bugzilla.kernel.org/show_bug.cgi?id=11529
James said that it might be better to disable interrupts inside the
function rather than risk the callers getting it wrong.
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
| -rw-r--r-- | lib/scatterlist.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/lib/scatterlist.c b/lib/scatterlist.c index b80c21100d78..8c11004ac347 100644 --- a/lib/scatterlist.c +++ b/lib/scatterlist.c @@ -312,8 +312,9 @@ static size_t sg_copy_buffer(struct scatterlist *sgl, unsigned int nents, struct scatterlist *sg; size_t buf_off = 0; int i; + unsigned long flags; - WARN_ON(!irqs_disabled()); + local_irq_save(flags); for_each_sg(sgl, sg, nents, i) { struct page *page; @@ -358,6 +359,8 @@ static size_t sg_copy_buffer(struct scatterlist *sgl, unsigned int nents, break; } + local_irq_restore(flags); + return buf_off; } |