From: Kevin Wolf Date: Tue, 29 Apr 2025 15:56:54 +0000 (+0200) Subject: file-posix: Fix crash on discard_granularity == 0 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=71a30d54e6ab1d5c102a8bee2c263414697402ea;p=thirdparty%2Fqemu.git file-posix: Fix crash on discard_granularity == 0 Block devices that don't support discard have a discard_granularity of 0. Currently, this results in a division by zero when we try to make sure that it's a multiple of request_alignment. Only try to update bs->bl.pdiscard_alignment when we got a non-zero discard_granularity from sysfs. Fixes: f605796aae4 ('file-posix: probe discard alignment on Linux block devices') Signed-off-by: Kevin Wolf Reviewed-by: Stefan Hajnoczi Reviewed-by: Eric Blake Message-ID: <20250429155654.102735-1-kwolf@redhat.com> Signed-off-by: Stefan Hajnoczi --- diff --git a/block/file-posix.c b/block/file-posix.c index 0d6e12f880..0d85123d0f 100644 --- a/block/file-posix.c +++ b/block/file-posix.c @@ -1573,7 +1573,7 @@ static void raw_refresh_limits(BlockDriverState *bs, Error **errp) int ret; ret = hdev_get_pdiscard_alignment(&st, &dalign); - if (ret == 0) { + if (ret == 0 && dalign != 0) { uint32_t ralign = bs->bl.request_alignment; /* Probably never happens, but handle it just in case */