On Thu, Jan 30, 2020 at 03:10:42PM +0300, Konstantin Khlebnikov wrote: > Please consider including into 4.19 upstream commits > > ba5d73851e71847ba7f7f4c27a1a6e1f5ab91c79 > ("block: cleanup __blkdev_issue_discard()") > > and > > 4800bf7bc8c725e955fcbc6191cc872f43f506d3 > ("block: fix 32 bit overflow in __blkdev_issue_discard()") THis patch does not apply to the 4.19 tree :( > Overflow of unsigned long "req_sects" (fixed in second patch) > actually exist here much longer. > > And 4.19 commit 744889b7cbb56a64f957e65ade7cb65fe3f35714 > ("block: don't deal with discard limit in blkdev_issue_discard()") > make it worse by replacing > > req_sects = min_t(sector_t, nr_sects, q->limits.max_discard_sectors); > > with > > unsigned int req_sects = nr_sects; > > > because now discard length isn't cut by max_discard_sectors it easily overflows. > As a result BLKDISCARD fails unexpectedly: > > ioctl(3, BLKDISCARD, [0, 0x20000000000]) = -1 EOPNOTSUPP (Operation not supported) I don't understand. Can you provide backported and working patches for the 4.19.y series so that I can apply them that way to show exactly what you have changed here? thanks, greg k-h