This is a note to let you know that I've just added the patch titled
dm cache: fix corruption seen when using cache > 2TB
to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
dm-cache-fix-corruption-seen-when-using-cache-2tb.patch
and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From ca763d0a53b264a650342cee206512bc92ac7050 Mon Sep 17 00:00:00 2001
From: Joe Thornber <ejt@xxxxxxxxxx>
Date: Thu, 9 Feb 2017 11:46:18 -0500
Subject: dm cache: fix corruption seen when using cache > 2TB
From: Joe Thornber <ejt@xxxxxxxxxx>
commit ca763d0a53b264a650342cee206512bc92ac7050 upstream.
A rounding bug due to compiler generated temporary being 32bit was found
in remap_to_cache(). A localized cast in remap_to_cache() fixes the
corruption but this preferred fix (changing from uint32_t to sector_t)
eliminates potential for future rounding errors elsewhere.
Signed-off-by: Joe Thornber <ejt@xxxxxxxxxx>
Signed-off-by: Mike Snitzer <snitzer@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/md/dm-cache-target.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
--- a/drivers/md/dm-cache-target.c
+++ b/drivers/md/dm-cache-target.c
@@ -251,7 +251,7 @@ struct cache {
/*
* Fields for converting from sectors to blocks.
*/
- uint32_t sectors_per_block;
+ sector_t sectors_per_block;
int sectors_per_block_shift;
spinlock_t lock;
@@ -3547,11 +3547,11 @@ static void cache_status(struct dm_targe
residency = policy_residency(cache->policy);
- DMEMIT("%u %llu/%llu %u %llu/%llu %u %u %u %u %u %u %lu ",
+ DMEMIT("%u %llu/%llu %llu %llu/%llu %u %u %u %u %u %u %lu ",
(unsigned)DM_CACHE_METADATA_BLOCK_SIZE,
(unsigned long long)(nr_blocks_metadata - nr_free_blocks_metadata),
(unsigned long long)nr_blocks_metadata,
- cache->sectors_per_block,
+ (unsigned long long)cache->sectors_per_block,
(unsigned long long) from_cblock(residency),
(unsigned long long) from_cblock(cache->cache_size),
(unsigned) atomic_read(&cache->stats.read_hit),
Patches currently in stable-queue which might be from ejt@xxxxxxxxxx are
queue-4.4/dm-cache-fix-corruption-seen-when-using-cache-2tb.patch