From: Alex Elder Date: Thu, 23 May 2013 01:54:25 +0000 (-0500) Subject: rbd: flush dcache after zeroing page data X-Git-Tag: v3.11-rc1~69^2~29 X-Git-Url: http://pileus.org/git/?p=~andy%2Flinux;a=commitdiff_plain;h=e215605417b87732c6debf65da6d953016a1e5bc rbd: flush dcache after zeroing page data Neither zero_bio_chain() nor zero_pages() contains a call to flush caches after zeroing a portion of a page. This can cause problems on architectures that have caches that allow virtual address aliasing. This resolves: http://tracker.ceph.com/issues/4777 Signed-off-by: Alex Elder Reviewed-by: Josh Durgin --- diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c index 291802c52c6..cb728a01a19 100644 --- a/drivers/block/rbd.c +++ b/drivers/block/rbd.c @@ -1126,6 +1126,7 @@ static void zero_bio_chain(struct bio *chain, int start_ofs) buf = bvec_kmap_irq(bv, &flags); memset(buf + remainder, 0, bv->bv_len - remainder); + flush_dcache_page(bv->bv_page); bvec_kunmap_irq(buf, &flags); } pos += bv->bv_len; @@ -1158,6 +1159,7 @@ static void zero_pages(struct page **pages, u64 offset, u64 end) local_irq_save(flags); kaddr = kmap_atomic(*page); memset(kaddr + page_offset, 0, length); + flush_dcache_page(*page); kunmap_atomic(kaddr); local_irq_restore(flags);