On Tue, Mar 16, 2021 at 06:47:39PM +0000, Luis Chamberlain wrote: > On Tue, Mar 16, 2021 at 05:46:45PM +0000, Luis Chamberlain wrote: > > I've managed to reproduce blktests block/009 failures with kdevops [0] > > on linux-next tag next-20210304 with a current failure rate average of > > 1/448 (3 counted failures so far). > > Confirmed on next-20210316 with current failure rate at 1/1008
Just in case this was a scsi_debug issue instead (I am covering that prospect on another bug just for scsi_debug korg#212337 [0]) I tried a userspace solution based on what I have observed I still can reproduce this block/009 failure. The failure rate is much lower though, I have it now at 1/1705 but alas it is still failing. [0] https://bugzilla.kernel.org/show_bug.cgi?id=212337 The patch below demonstrates the exra settle work for scsi_debug attempted, and with it, this is still failing. So either the settle work needs *more* effort, or this is a real issue. diff --git a/common/scsi_debug b/common/scsi_debug index b48cdc9..ecdbcc6 100644 --- a/common/scsi_debug +++ b/common/scsi_debug @@ -8,13 +8,42 @@ _have_scsi_debug() { _have_modules scsi_debug } +# As per korg#212337 [0] we must do more work in userspace to settle +# scsi_debug devices a bit more carefully. + +# [0] https://bugzilla.kernel.org/show_bug.cgi?id=212337 +_settle_scsi_debug_device() { + SCSI_DEBUG_MAX_WAIT=10 + SCSI_DEBUG_COUNT_WAIT_LOOP=0 + while true ; do + if [[ -b $1 ]]; then + SCSI_DEBUG_LSOF_COUNT=$(lsof $1 | wc -l) + if [[ $SCSI_DEBUG_LSOF_COUNT -ne 0 ]]; then + sleep 1; + else + break + fi + else + # Let device come up + sleep 1 + + let SCSI_DEBUG_COUNT_WAIT_LOOP=$SCSI_DEBUG_COUNT_WAIT_LOOP+1 + if [[ $SCSI_DEBUG_COUNT_WAIT_LOOP -ge $SCSI_DEBUG_MAX_WAIT ]]; then + break + fi + fi + done +} + _init_scsi_debug() { if ! modprobe -r scsi_debug || ! modprobe scsi_debug "$@"; then return 1 fi - udevadm settle + # Allow dependencies to load + sleep 1 + local host_sysfs host target_sysfs target SCSI_DEBUG_HOSTS=() SCSI_DEBUG_TARGETS=() @@ -43,6 +72,10 @@ _init_scsi_debug() { return 1 fi + for i in $SCSI_DEBUG_DEVICES ; do + _settle_scsi_debug_device /dev/$i + done + return 0 }
