The patch titled
aoe: prevent cache aliases
has been added to the -mm tree. Its filename is
aoe-prevent-cache-aliases.patch
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------------------------------------------------------
Subject: aoe: prevent cache aliases
From: Peter Horton <phorton@xxxxxxxxxxxx>
Prevent the AoE block driver from creating cache aliases of page cache
pages on machines with virtually indexed caches.
Building kernels on an AT91SAM9G20 board without this patch fails with
segmentation faults after a couple of passes.
Signed-off-by: Peter Horton <zero@xxxxxxxxxxxxxxxxx>
Cc: "Ed L. Cashin" <ecashin@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
diff -puN drivers/block/aoe/aoecmd.c~aoe-prevent-cache-aliases drivers/block/aoe/aoecmd.c
--- a/drivers/block/aoe/aoecmd.c~aoe-prevent-cache-aliases
+++ a/drivers/block/aoe/aoecmd.c
@@ -735,6 +735,21 @@ diskstats(struct gendisk *disk, struct b
part_stat_unlock();
}
+/*
+ * Ensure we don't create aliases in VI caches
+ */
+static inline void
+killalias(struct bio *bio)
+{
+ struct bio_vec *bv;
+ int i;
+
+ if (bio_data_dir(bio) == READ)
+ __bio_for_each_segment(bv, bio, i, 0) {
+ flush_dcache_page(bv->bv_page);
+ }
+}
+
void
aoecmd_ata_rsp(struct sk_buff *skb)
{
@@ -853,8 +868,12 @@ aoecmd_ata_rsp(struct sk_buff *skb)
if (buf && --buf->nframesout == 0 && buf->resid == 0) {
diskstats(d->gd, buf->bio, jiffies - buf->stime, buf->sector);
- n = (buf->flags & BUFFL_FAIL) ? -EIO : 0;
- bio_endio(buf->bio, n);
+ if (buf->flags & BUFFL_FAIL)
+ bio_endio(buf->bio, -EIO);
+ else {
+ killalias(buf->bio);
+ bio_endio(buf->bio, 0);
+ }
mempool_free(buf, d->bufpool);
}
_
Patches currently in -mm which might be from phorton@xxxxxxxxxxxx are
aoe-prevent-cache-aliases.patch
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