The patch below does not apply to the 5.4-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.4.y git checkout FETCH_HEAD git cherry-pick -x 8eb29c4fbf9661e6bd4dd86197a37ffe0ecc9d50 # <resolve conflicts, build, test, etc.> git commit -s git send-email --to 'stable@vger.kernel.org' --in-reply-to '167819226210440@kroah.com' --subject-prefix 'PATCH 5.4.y' HEAD^..

Possible dependencies:

8eb29c4fbf96 ("dm flakey: fix a bug with 32-bit highmem systems") f50714b57aec ("dm flakey: don't corrupt the zero page")

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 8eb29c4fbf9661e6bd4dd86197a37ffe0ecc9d50 Mon Sep 17 00:00:00 2001 From: Mikulas Patocka mpatocka@redhat.com Date: Sun, 22 Jan 2023 14:03:31 -0500 Subject: [PATCH] dm flakey: fix a bug with 32-bit highmem systems

The function page_address does not work with 32-bit systems with high memory. Use bvec_kmap_local/kunmap_local instead.

Cc: stable@vger.kernel.org Signed-off-by: Mikulas Patocka mpatocka@redhat.com Reviewed-by: Sweet Tea Dorminy sweettea-kernel@dorminy.me Signed-off-by: Mike Snitzer snitzer@kernel.org

diff --git a/drivers/md/dm-flakey.c b/drivers/md/dm-flakey.c index ff9ca5b2a47e..33608d436cec 100644 --- a/drivers/md/dm-flakey.c +++ b/drivers/md/dm-flakey.c @@ -307,8 +307,9 @@ static void corrupt_bio_data(struct bio *bio, struct flakey_c *fc) struct page *page = bio_iter_page(bio, iter); if (unlikely(page == ZERO_PAGE(0))) break; - segment = (page_address(page) + bio_iter_offset(bio, iter)); + segment = bvec_kmap_local(&bvec); segment[corrupt_bio_byte] = fc->corrupt_bio_value; + kunmap_local(segment); DMDEBUG("Corrupting data bio=%p by writing %u to byte %u " "(rw=%c bi_opf=%u bi_sector=%llu size=%u)\n", bio, fc->corrupt_bio_value, fc->corrupt_bio_byte,