In binutils 2.26 a new opcode for the "wait" instruction was added for the
POWER9 and has precedence over the one specific to the e500mc. Commit
ebf714ff3756 ("powerpc/e500mc: Add support for the wait instruction in
e500_idle") uses this instruction specifically on the e500mc to work around
an erratum.
This results in an invalid instruction in idle_e500 when we build for the
e500mc on bintutils >= 2.26 with the default assembler machine type.
Since multiplatform between e500 and non-e500 is not supported, set the
assembler machine type globaly when CONFIG_PPC_E500MC=y.
Signed-off-by: Michael Jeanson <mjeanson(a)efficios.com>
Reviewed-by: Mathieu Desnoyers <mathieu.desnoyers(a)efficios.com>
CC: Benjamin Herrenschmidt <benh(a)kernel.crashing.org>
CC: Paul Mackerras <paulus(a)samba.org>
CC: Michael Ellerman <mpe(a)ellerman.id.au>
CC: Kumar Gala <galak(a)kernel.crashing.org>
CC: Vakul Garg <vakul.garg(a)nxp.com>
CC: Scott Wood <swood(a)redhat.com>
CC: Mathieu Desnoyers <mathieu.desnoyers(a)efficios.com>
CC: linuxppc-dev(a)lists.ozlabs.org
CC: linux-kernel(a)vger.kernel.org
CC: stable(a)vger.kernel.org
---
arch/powerpc/Makefile | 1 +
1 file changed, 1 insertion(+)
diff --git a/arch/powerpc/Makefile b/arch/powerpc/Makefile
index 95813df90801..bb2523b4bd8f 100644
--- a/arch/powerpc/Makefile
+++ b/arch/powerpc/Makefile
@@ -251,6 +251,7 @@ cpu-as-$(CONFIG_4xx) += -Wa,-m405
cpu-as-$(CONFIG_ALTIVEC) += $(call as-option,-Wa$(comma)-maltivec)
cpu-as-$(CONFIG_E200) += -Wa,-me200
cpu-as-$(CONFIG_PPC_BOOK3S_64) += -Wa,-mpower4
+cpu-as-$(CONFIG_PPC_E500MC) += $(call as-option,-Wa$(comma)-me500mc)
KBUILD_AFLAGS += $(cpu-as-y)
KBUILD_CFLAGS += $(cpu-as-y)
--
2.17.1
From: Alan Jenkins <alan.christopher.jenkins(a)gmail.com>
BugLink: http://bugs.launchpad.net/bugs/1776887
When blk_queue_enter() waits for a queue to unfreeze, or unset the
PREEMPT_ONLY flag, do not allow it to be interrupted by a signal.
The PREEMPT_ONLY flag was introduced later in commit 3a0a529971ec
("block, scsi: Make SCSI quiesce and resume work reliably"). Note the SCSI
device is resumed asynchronously, i.e. after un-freezing userspace tasks.
So that commit exposed the bug as a regression in v4.15. A mysterious
SIGBUS (or -EIO) sometimes happened during the time the device was being
resumed. Most frequently, there was no kernel log message, and we saw Xorg
or Xwayland killed by SIGBUS.[1]
[1] E.g. https://bugzilla.redhat.com/show_bug.cgi?id=1553979
Without this fix, I get an IO error in this test:
# dd if=/dev/sda of=/dev/null iflag=direct & \
while killall -SIGUSR1 dd; do sleep 0.1; done & \
echo mem > /sys/power/state ; \
sleep 5; killall dd # stop after 5 seconds
The interruptible wait was added to blk_queue_enter in
commit 3ef28e83ab15 ("block: generic request_queue reference counting").
Before then, the interruptible wait was only in blk-mq, but I don't think
it could ever have been correct.
Reviewed-by: Bart Van Assche <bart.vanassche(a)wdc.com>
Cc: stable(a)vger.kernel.org
Signed-off-by: Alan Jenkins <alan.christopher.jenkins(a)gmail.com>
Signed-off-by: Jens Axboe <axboe(a)kernel.dk>
(cherry-picked from 1dc3039bc87ae7d19a990c3ee71cfd8a9068f428)
Signed-off-by: Khalid Elmously <khalid.elmously(a)canonical.com>
---
block/blk-core.c | 11 ++++-------
1 file changed, 4 insertions(+), 7 deletions(-)
diff --git a/block/blk-core.c b/block/blk-core.c
index fc0666354af3..59c91e345eea 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -821,7 +821,6 @@ int blk_queue_enter(struct request_queue *q, blk_mq_req_flags_t flags)
while (true) {
bool success = false;
- int ret;
rcu_read_lock();
if (percpu_ref_tryget_live(&q->q_usage_counter)) {
@@ -853,14 +852,12 @@ int blk_queue_enter(struct request_queue *q, blk_mq_req_flags_t flags)
*/
smp_rmb();
- ret = wait_event_interruptible(q->mq_freeze_wq,
- (atomic_read(&q->mq_freeze_depth) == 0 &&
- (preempt || !blk_queue_preempt_only(q))) ||
- blk_queue_dying(q));
+ wait_event(q->mq_freeze_wq,
+ (atomic_read(&q->mq_freeze_depth) == 0 &&
+ (preempt || !blk_queue_preempt_only(q))) ||
+ blk_queue_dying(q));
if (blk_queue_dying(q))
return -ENODEV;
- if (ret)
- return ret;
}
}
--
2.17.1
From: Alan Jenkins <alan.christopher.jenkins(a)gmail.com>
BugLink: http://bugs.launchpad.net/bugs/1776887
When blk_queue_enter() waits for a queue to unfreeze, or unset the
PREEMPT_ONLY flag, do not allow it to be interrupted by a signal.
The PREEMPT_ONLY flag was introduced later in commit 3a0a529971ec
("block, scsi: Make SCSI quiesce and resume work reliably"). Note the SCSI
device is resumed asynchronously, i.e. after un-freezing userspace tasks.
So that commit exposed the bug as a regression in v4.15. A mysterious
SIGBUS (or -EIO) sometimes happened during the time the device was being
resumed. Most frequently, there was no kernel log message, and we saw Xorg
or Xwayland killed by SIGBUS.[1]
[1] E.g. https://bugzilla.redhat.com/show_bug.cgi?id=1553979
Without this fix, I get an IO error in this test:
# dd if=/dev/sda of=/dev/null iflag=direct & \
while killall -SIGUSR1 dd; do sleep 0.1; done & \
echo mem > /sys/power/state ; \
sleep 5; killall dd # stop after 5 seconds
The interruptible wait was added to blk_queue_enter in
commit 3ef28e83ab15 ("block: generic request_queue reference counting").
Before then, the interruptible wait was only in blk-mq, but I don't think
it could ever have been correct.
Reviewed-by: Bart Van Assche <bart.vanassche(a)wdc.com>
Cc: stable(a)vger.kernel.org
Signed-off-by: Alan Jenkins <alan.christopher.jenkins(a)gmail.com>
Signed-off-by: Jens Axboe <axboe(a)kernel.dk>
(cherry-picked from 1dc3039bc87ae7d19a990c3ee71cfd8a9068f428)
Signed-off-by: Khalid Elmously <khalid.elmously(a)canonical.com>
---
block/blk-core.c | 11 ++++-------
1 file changed, 4 insertions(+), 7 deletions(-)
diff --git a/block/blk-core.c b/block/blk-core.c
index fc0666354af3..59c91e345eea 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -821,7 +821,6 @@ int blk_queue_enter(struct request_queue *q, blk_mq_req_flags_t flags)
while (true) {
bool success = false;
- int ret;
rcu_read_lock();
if (percpu_ref_tryget_live(&q->q_usage_counter)) {
@@ -853,14 +852,12 @@ int blk_queue_enter(struct request_queue *q, blk_mq_req_flags_t flags)
*/
smp_rmb();
- ret = wait_event_interruptible(q->mq_freeze_wq,
- (atomic_read(&q->mq_freeze_depth) == 0 &&
- (preempt || !blk_queue_preempt_only(q))) ||
- blk_queue_dying(q));
+ wait_event(q->mq_freeze_wq,
+ (atomic_read(&q->mq_freeze_depth) == 0 &&
+ (preempt || !blk_queue_preempt_only(q))) ||
+ blk_queue_dying(q));
if (blk_queue_dying(q))
return -ENODEV;
- if (ret)
- return ret;
}
}
--
2.17.1
On Wed, 2018-02-28 at 09:19 +0000, Roger Pau Monne wrote:
> From: Roger Pau Monne <roger.pau(a)citrix.com>
>
> [ Upstream commit 910f8befdf5bccf25287d9f1743e3e546bcb7ce0 ]
>
> Current cleanup in the error path of xen_bind_pirq_msi_to_irq is
> wrong. First of all there's an off-by-one in the cleanup loop, which
> can lead to unbinding wrong IRQs.
>
> Secondly IRQs not bound won't be freed, thus leaking IRQ numbers.
>
> Note that there's no need to differentiate between bound and unbound
> IRQs when freeing them, __unbind_from_irq will deal with both of them
> correctly.
It appears to me that it is safe to call __unbind_from_irq() after
xen_irq_info_common_setup() fails, but *not* if the latter hasn't been
called at all. In that case the IRQ type will still be set to
IRQT_UNBOUND and this will trigger the BUG_ON() in __unbind_from_irq().
[...]
> --- a/drivers/xen/events/events_base.c
> +++ b/drivers/xen/events/events_base.c
> @@ -764,8 +764,8 @@ out:
> mutex_unlock(&irq_mapping_update_lock);
> return irq;
> error_irq:
> - for (; i >= 0; i--)
> - __unbind_from_irq(irq + i);
> + while (nvec--)
> + __unbind_from_irq(irq + nvec);
If nvec > 1, and xen_irq_info_pirq_setup() fails for i != nvec - 1,
then we reach here without having called xen_irq_info_common_setup()
for all these IRQs.
In that case, I think we will still want to call xen_free_irq() for all
IRQs. So maybe the fix would be to remove the BUG_ON() in
__unbind_from_irq()?
Ben.
> mutex_unlock(&irq_mapping_update_lock);
> return ret;
> }
--
Ben Hutchings, Software Developer Codethink Ltd
https://www.codethink.co.uk/ Dale House, 35 Dale Street
Manchester, M1 2HF, United Kingdom