The patch below does not apply to the 4.4-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(a)vger.kernel.org>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From 7f5203c13ba8a7b7f9f6ecfe5a4d5567188d7835 Mon Sep 17 00:00:00 2001
From: Tyrel Datwyler <tyreld(a)linux.vnet.ibm.com>
Date: Wed, 20 Mar 2019 13:41:51 -0500
Subject: [PATCH] scsi: ibmvscsi: Fix empty event pool access during host
removal
The event pool used for queueing commands is destroyed fairly early in the
ibmvscsi_remove() code path. Since, this happens prior to the call so
scsi_remove_host() it is possible for further calls to queuecommand to be
processed which manifest as a panic due to a NULL pointer dereference as
seen here:
PANIC: "Unable to handle kernel paging request for data at address
0x00000000"
Context process backtrace:
DSISR: 0000000042000000 ????Syscall Result: 0000000000000000
4 [c000000002cb3820] memcpy_power7 at c000000000064204
[Link Register] [c000000002cb3820] ibmvscsi_send_srp_event at d000000003ed14a4
5 [c000000002cb3920] ibmvscsi_send_srp_event at d000000003ed14a4 [ibmvscsi] ?(unreliable)
6 [c000000002cb39c0] ibmvscsi_queuecommand at d000000003ed2388 [ibmvscsi]
7 [c000000002cb3a70] scsi_dispatch_cmd at d00000000395c2d8 [scsi_mod]
8 [c000000002cb3af0] scsi_request_fn at d00000000395ef88 [scsi_mod]
9 [c000000002cb3be0] __blk_run_queue at c000000000429860
10 [c000000002cb3c10] blk_delay_work at c00000000042a0ec
11 [c000000002cb3c40] process_one_work at c0000000000dac30
12 [c000000002cb3cd0] worker_thread at c0000000000db110
13 [c000000002cb3d80] kthread at c0000000000e3378
14 [c000000002cb3e30] ret_from_kernel_thread at c00000000000982c
The kernel buffer log is overfilled with this log:
[11261.952732] ibmvscsi: found no event struct in pool!
This patch reorders the operations during host teardown. Start by calling
the SRP transport and Scsi_Host remove functions to flush any outstanding
work and set the host offline. LLDD teardown follows including destruction
of the event pool, freeing the Command Response Queue (CRQ), and unmapping
any persistent buffers. The event pool destruction is protected by the
scsi_host lock, and the pool is purged prior of any requests for which we
never received a response. Finally, move the removal of the scsi host from
our global list to the end so that the host is easily locatable for
debugging purposes during teardown.
Cc: <stable(a)vger.kernel.org> # v2.6.12+
Signed-off-by: Tyrel Datwyler <tyreld(a)linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen(a)oracle.com>
diff --git a/drivers/scsi/ibmvscsi/ibmvscsi.c b/drivers/scsi/ibmvscsi/ibmvscsi.c
index 2b22969f3f63..8cec5230fe31 100644
--- a/drivers/scsi/ibmvscsi/ibmvscsi.c
+++ b/drivers/scsi/ibmvscsi/ibmvscsi.c
@@ -2295,17 +2295,27 @@ static int ibmvscsi_probe(struct vio_dev *vdev, const struct vio_device_id *id)
static int ibmvscsi_remove(struct vio_dev *vdev)
{
struct ibmvscsi_host_data *hostdata = dev_get_drvdata(&vdev->dev);
- spin_lock(&ibmvscsi_driver_lock);
- list_del(&hostdata->host_list);
- spin_unlock(&ibmvscsi_driver_lock);
- unmap_persist_bufs(hostdata);
+ unsigned long flags;
+
+ srp_remove_host(hostdata->host);
+ scsi_remove_host(hostdata->host);
+
+ purge_requests(hostdata, DID_ERROR);
+
+ spin_lock_irqsave(hostdata->host->host_lock, flags);
release_event_pool(&hostdata->pool, hostdata);
+ spin_unlock_irqrestore(hostdata->host->host_lock, flags);
+
ibmvscsi_release_crq_queue(&hostdata->queue, hostdata,
max_events);
kthread_stop(hostdata->work_thread);
- srp_remove_host(hostdata->host);
- scsi_remove_host(hostdata->host);
+ unmap_persist_bufs(hostdata);
+
+ spin_lock(&ibmvscsi_driver_lock);
+ list_del(&hostdata->host_list);
+ spin_unlock(&ibmvscsi_driver_lock);
+
scsi_host_put(hostdata->host);
return 0;
The patch below does not apply to the 4.9-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(a)vger.kernel.org>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From 7f5203c13ba8a7b7f9f6ecfe5a4d5567188d7835 Mon Sep 17 00:00:00 2001
From: Tyrel Datwyler <tyreld(a)linux.vnet.ibm.com>
Date: Wed, 20 Mar 2019 13:41:51 -0500
Subject: [PATCH] scsi: ibmvscsi: Fix empty event pool access during host
removal
The event pool used for queueing commands is destroyed fairly early in the
ibmvscsi_remove() code path. Since, this happens prior to the call so
scsi_remove_host() it is possible for further calls to queuecommand to be
processed which manifest as a panic due to a NULL pointer dereference as
seen here:
PANIC: "Unable to handle kernel paging request for data at address
0x00000000"
Context process backtrace:
DSISR: 0000000042000000 ????Syscall Result: 0000000000000000
4 [c000000002cb3820] memcpy_power7 at c000000000064204
[Link Register] [c000000002cb3820] ibmvscsi_send_srp_event at d000000003ed14a4
5 [c000000002cb3920] ibmvscsi_send_srp_event at d000000003ed14a4 [ibmvscsi] ?(unreliable)
6 [c000000002cb39c0] ibmvscsi_queuecommand at d000000003ed2388 [ibmvscsi]
7 [c000000002cb3a70] scsi_dispatch_cmd at d00000000395c2d8 [scsi_mod]
8 [c000000002cb3af0] scsi_request_fn at d00000000395ef88 [scsi_mod]
9 [c000000002cb3be0] __blk_run_queue at c000000000429860
10 [c000000002cb3c10] blk_delay_work at c00000000042a0ec
11 [c000000002cb3c40] process_one_work at c0000000000dac30
12 [c000000002cb3cd0] worker_thread at c0000000000db110
13 [c000000002cb3d80] kthread at c0000000000e3378
14 [c000000002cb3e30] ret_from_kernel_thread at c00000000000982c
The kernel buffer log is overfilled with this log:
[11261.952732] ibmvscsi: found no event struct in pool!
This patch reorders the operations during host teardown. Start by calling
the SRP transport and Scsi_Host remove functions to flush any outstanding
work and set the host offline. LLDD teardown follows including destruction
of the event pool, freeing the Command Response Queue (CRQ), and unmapping
any persistent buffers. The event pool destruction is protected by the
scsi_host lock, and the pool is purged prior of any requests for which we
never received a response. Finally, move the removal of the scsi host from
our global list to the end so that the host is easily locatable for
debugging purposes during teardown.
Cc: <stable(a)vger.kernel.org> # v2.6.12+
Signed-off-by: Tyrel Datwyler <tyreld(a)linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen(a)oracle.com>
diff --git a/drivers/scsi/ibmvscsi/ibmvscsi.c b/drivers/scsi/ibmvscsi/ibmvscsi.c
index 2b22969f3f63..8cec5230fe31 100644
--- a/drivers/scsi/ibmvscsi/ibmvscsi.c
+++ b/drivers/scsi/ibmvscsi/ibmvscsi.c
@@ -2295,17 +2295,27 @@ static int ibmvscsi_probe(struct vio_dev *vdev, const struct vio_device_id *id)
static int ibmvscsi_remove(struct vio_dev *vdev)
{
struct ibmvscsi_host_data *hostdata = dev_get_drvdata(&vdev->dev);
- spin_lock(&ibmvscsi_driver_lock);
- list_del(&hostdata->host_list);
- spin_unlock(&ibmvscsi_driver_lock);
- unmap_persist_bufs(hostdata);
+ unsigned long flags;
+
+ srp_remove_host(hostdata->host);
+ scsi_remove_host(hostdata->host);
+
+ purge_requests(hostdata, DID_ERROR);
+
+ spin_lock_irqsave(hostdata->host->host_lock, flags);
release_event_pool(&hostdata->pool, hostdata);
+ spin_unlock_irqrestore(hostdata->host->host_lock, flags);
+
ibmvscsi_release_crq_queue(&hostdata->queue, hostdata,
max_events);
kthread_stop(hostdata->work_thread);
- srp_remove_host(hostdata->host);
- scsi_remove_host(hostdata->host);
+ unmap_persist_bufs(hostdata);
+
+ spin_lock(&ibmvscsi_driver_lock);
+ list_del(&hostdata->host_list);
+ spin_unlock(&ibmvscsi_driver_lock);
+
scsi_host_put(hostdata->host);
return 0;
The patch below does not apply to the 4.4-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(a)vger.kernel.org>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From 17605afaae825b0291f80c62a7f6565879edaa8a Mon Sep 17 00:00:00 2001
From: Bart Van Assche <bvanassche(a)acm.org>
Date: Fri, 15 Mar 2019 16:27:58 -0700
Subject: [PATCH] scsi: core: Avoid that a kernel warning appears during system
resume
Since scsi_device_quiesce() skips SCSI devices that have another state than
RUNNING, OFFLINE or TRANSPORT_OFFLINE, scsi_device_resume() should not
complain about SCSI devices that have been skipped. Hence this patch. This
patch avoids that the following warning appears during resume:
WARNING: CPU: 3 PID: 1039 at blk_clear_pm_only+0x2a/0x30
CPU: 3 PID: 1039 Comm: kworker/u8:49 Not tainted 5.0.0+ #1
Hardware name: LENOVO 4180F42/4180F42, BIOS 83ET75WW (1.45 ) 05/10/2013
Workqueue: events_unbound async_run_entry_fn
RIP: 0010:blk_clear_pm_only+0x2a/0x30
Call Trace:
? scsi_device_resume+0x28/0x50
? scsi_dev_type_resume+0x2b/0x80
? async_run_entry_fn+0x2c/0xd0
? process_one_work+0x1f0/0x3f0
? worker_thread+0x28/0x3c0
? process_one_work+0x3f0/0x3f0
? kthread+0x10c/0x130
? __kthread_create_on_node+0x150/0x150
? ret_from_fork+0x1f/0x30
Cc: Christoph Hellwig <hch(a)lst.de>
Cc: Hannes Reinecke <hare(a)suse.com>
Cc: Ming Lei <ming.lei(a)redhat.com>
Cc: Johannes Thumshirn <jthumshirn(a)suse.de>
Cc: Oleksandr Natalenko <oleksandr(a)natalenko.name>
Cc: Martin Steigerwald <martin(a)lichtvoll.de>
Cc: <stable(a)vger.kernel.org>
Reported-by: Jisheng Zhang <Jisheng.Zhang(a)synaptics.com>
Tested-by: Jisheng Zhang <Jisheng.Zhang(a)synaptics.com>
Fixes: 3a0a529971ec ("block, scsi: Make SCSI quiesce and resume work reliably") # v4.15
Signed-off-by: Bart Van Assche <bvanassche(a)acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen(a)oracle.com>
diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index f0db2dd0be75..601b9f1de267 100644
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -2548,8 +2548,10 @@ void scsi_device_resume(struct scsi_device *sdev)
* device deleted during suspend)
*/
mutex_lock(&sdev->state_mutex);
- sdev->quiesced_by = NULL;
- blk_clear_pm_only(sdev->request_queue);
+ if (sdev->quiesced_by) {
+ sdev->quiesced_by = NULL;
+ blk_clear_pm_only(sdev->request_queue);
+ }
if (sdev->sdev_state == SDEV_QUIESCE)
scsi_device_set_state(sdev, SDEV_RUNNING);
mutex_unlock(&sdev->state_mutex);
The patch below does not apply to the 4.9-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(a)vger.kernel.org>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From 17605afaae825b0291f80c62a7f6565879edaa8a Mon Sep 17 00:00:00 2001
From: Bart Van Assche <bvanassche(a)acm.org>
Date: Fri, 15 Mar 2019 16:27:58 -0700
Subject: [PATCH] scsi: core: Avoid that a kernel warning appears during system
resume
Since scsi_device_quiesce() skips SCSI devices that have another state than
RUNNING, OFFLINE or TRANSPORT_OFFLINE, scsi_device_resume() should not
complain about SCSI devices that have been skipped. Hence this patch. This
patch avoids that the following warning appears during resume:
WARNING: CPU: 3 PID: 1039 at blk_clear_pm_only+0x2a/0x30
CPU: 3 PID: 1039 Comm: kworker/u8:49 Not tainted 5.0.0+ #1
Hardware name: LENOVO 4180F42/4180F42, BIOS 83ET75WW (1.45 ) 05/10/2013
Workqueue: events_unbound async_run_entry_fn
RIP: 0010:blk_clear_pm_only+0x2a/0x30
Call Trace:
? scsi_device_resume+0x28/0x50
? scsi_dev_type_resume+0x2b/0x80
? async_run_entry_fn+0x2c/0xd0
? process_one_work+0x1f0/0x3f0
? worker_thread+0x28/0x3c0
? process_one_work+0x3f0/0x3f0
? kthread+0x10c/0x130
? __kthread_create_on_node+0x150/0x150
? ret_from_fork+0x1f/0x30
Cc: Christoph Hellwig <hch(a)lst.de>
Cc: Hannes Reinecke <hare(a)suse.com>
Cc: Ming Lei <ming.lei(a)redhat.com>
Cc: Johannes Thumshirn <jthumshirn(a)suse.de>
Cc: Oleksandr Natalenko <oleksandr(a)natalenko.name>
Cc: Martin Steigerwald <martin(a)lichtvoll.de>
Cc: <stable(a)vger.kernel.org>
Reported-by: Jisheng Zhang <Jisheng.Zhang(a)synaptics.com>
Tested-by: Jisheng Zhang <Jisheng.Zhang(a)synaptics.com>
Fixes: 3a0a529971ec ("block, scsi: Make SCSI quiesce and resume work reliably") # v4.15
Signed-off-by: Bart Van Assche <bvanassche(a)acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen(a)oracle.com>
diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index f0db2dd0be75..601b9f1de267 100644
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -2548,8 +2548,10 @@ void scsi_device_resume(struct scsi_device *sdev)
* device deleted during suspend)
*/
mutex_lock(&sdev->state_mutex);
- sdev->quiesced_by = NULL;
- blk_clear_pm_only(sdev->request_queue);
+ if (sdev->quiesced_by) {
+ sdev->quiesced_by = NULL;
+ blk_clear_pm_only(sdev->request_queue);
+ }
if (sdev->sdev_state == SDEV_QUIESCE)
scsi_device_set_state(sdev, SDEV_RUNNING);
mutex_unlock(&sdev->state_mutex);
The patch below does not apply to the 4.14-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(a)vger.kernel.org>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From 17605afaae825b0291f80c62a7f6565879edaa8a Mon Sep 17 00:00:00 2001
From: Bart Van Assche <bvanassche(a)acm.org>
Date: Fri, 15 Mar 2019 16:27:58 -0700
Subject: [PATCH] scsi: core: Avoid that a kernel warning appears during system
resume
Since scsi_device_quiesce() skips SCSI devices that have another state than
RUNNING, OFFLINE or TRANSPORT_OFFLINE, scsi_device_resume() should not
complain about SCSI devices that have been skipped. Hence this patch. This
patch avoids that the following warning appears during resume:
WARNING: CPU: 3 PID: 1039 at blk_clear_pm_only+0x2a/0x30
CPU: 3 PID: 1039 Comm: kworker/u8:49 Not tainted 5.0.0+ #1
Hardware name: LENOVO 4180F42/4180F42, BIOS 83ET75WW (1.45 ) 05/10/2013
Workqueue: events_unbound async_run_entry_fn
RIP: 0010:blk_clear_pm_only+0x2a/0x30
Call Trace:
? scsi_device_resume+0x28/0x50
? scsi_dev_type_resume+0x2b/0x80
? async_run_entry_fn+0x2c/0xd0
? process_one_work+0x1f0/0x3f0
? worker_thread+0x28/0x3c0
? process_one_work+0x3f0/0x3f0
? kthread+0x10c/0x130
? __kthread_create_on_node+0x150/0x150
? ret_from_fork+0x1f/0x30
Cc: Christoph Hellwig <hch(a)lst.de>
Cc: Hannes Reinecke <hare(a)suse.com>
Cc: Ming Lei <ming.lei(a)redhat.com>
Cc: Johannes Thumshirn <jthumshirn(a)suse.de>
Cc: Oleksandr Natalenko <oleksandr(a)natalenko.name>
Cc: Martin Steigerwald <martin(a)lichtvoll.de>
Cc: <stable(a)vger.kernel.org>
Reported-by: Jisheng Zhang <Jisheng.Zhang(a)synaptics.com>
Tested-by: Jisheng Zhang <Jisheng.Zhang(a)synaptics.com>
Fixes: 3a0a529971ec ("block, scsi: Make SCSI quiesce and resume work reliably") # v4.15
Signed-off-by: Bart Van Assche <bvanassche(a)acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen(a)oracle.com>
diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index f0db2dd0be75..601b9f1de267 100644
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -2548,8 +2548,10 @@ void scsi_device_resume(struct scsi_device *sdev)
* device deleted during suspend)
*/
mutex_lock(&sdev->state_mutex);
- sdev->quiesced_by = NULL;
- blk_clear_pm_only(sdev->request_queue);
+ if (sdev->quiesced_by) {
+ sdev->quiesced_by = NULL;
+ blk_clear_pm_only(sdev->request_queue);
+ }
if (sdev->sdev_state == SDEV_QUIESCE)
scsi_device_set_state(sdev, SDEV_RUNNING);
mutex_unlock(&sdev->state_mutex);
The patch below does not apply to the 4.19-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(a)vger.kernel.org>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From 17605afaae825b0291f80c62a7f6565879edaa8a Mon Sep 17 00:00:00 2001
From: Bart Van Assche <bvanassche(a)acm.org>
Date: Fri, 15 Mar 2019 16:27:58 -0700
Subject: [PATCH] scsi: core: Avoid that a kernel warning appears during system
resume
Since scsi_device_quiesce() skips SCSI devices that have another state than
RUNNING, OFFLINE or TRANSPORT_OFFLINE, scsi_device_resume() should not
complain about SCSI devices that have been skipped. Hence this patch. This
patch avoids that the following warning appears during resume:
WARNING: CPU: 3 PID: 1039 at blk_clear_pm_only+0x2a/0x30
CPU: 3 PID: 1039 Comm: kworker/u8:49 Not tainted 5.0.0+ #1
Hardware name: LENOVO 4180F42/4180F42, BIOS 83ET75WW (1.45 ) 05/10/2013
Workqueue: events_unbound async_run_entry_fn
RIP: 0010:blk_clear_pm_only+0x2a/0x30
Call Trace:
? scsi_device_resume+0x28/0x50
? scsi_dev_type_resume+0x2b/0x80
? async_run_entry_fn+0x2c/0xd0
? process_one_work+0x1f0/0x3f0
? worker_thread+0x28/0x3c0
? process_one_work+0x3f0/0x3f0
? kthread+0x10c/0x130
? __kthread_create_on_node+0x150/0x150
? ret_from_fork+0x1f/0x30
Cc: Christoph Hellwig <hch(a)lst.de>
Cc: Hannes Reinecke <hare(a)suse.com>
Cc: Ming Lei <ming.lei(a)redhat.com>
Cc: Johannes Thumshirn <jthumshirn(a)suse.de>
Cc: Oleksandr Natalenko <oleksandr(a)natalenko.name>
Cc: Martin Steigerwald <martin(a)lichtvoll.de>
Cc: <stable(a)vger.kernel.org>
Reported-by: Jisheng Zhang <Jisheng.Zhang(a)synaptics.com>
Tested-by: Jisheng Zhang <Jisheng.Zhang(a)synaptics.com>
Fixes: 3a0a529971ec ("block, scsi: Make SCSI quiesce and resume work reliably") # v4.15
Signed-off-by: Bart Van Assche <bvanassche(a)acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen(a)oracle.com>
diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index f0db2dd0be75..601b9f1de267 100644
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -2548,8 +2548,10 @@ void scsi_device_resume(struct scsi_device *sdev)
* device deleted during suspend)
*/
mutex_lock(&sdev->state_mutex);
- sdev->quiesced_by = NULL;
- blk_clear_pm_only(sdev->request_queue);
+ if (sdev->quiesced_by) {
+ sdev->quiesced_by = NULL;
+ blk_clear_pm_only(sdev->request_queue);
+ }
if (sdev->sdev_state == SDEV_QUIESCE)
scsi_device_set_state(sdev, SDEV_RUNNING);
mutex_unlock(&sdev->state_mutex);
The patch below does not apply to the 4.19-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(a)vger.kernel.org>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From 92edf8df0ff2ae86cc632eeca0e651fd8431d40d Mon Sep 17 00:00:00 2001
From: Michael Ellerman <mpe(a)ellerman.id.au>
Date: Thu, 21 Mar 2019 15:24:33 +1100
Subject: [PATCH] powerpc/security: Fix spectre_v2 reporting
When I updated the spectre_v2 reporting to handle software count cache
flush I got the logic wrong when there's no software count cache
enabled at all.
The result is that on systems with the software count cache flush
disabled we print:
Mitigation: Indirect branch cache disabled, Software count cache flush
Which correctly indicates that the count cache is disabled, but
incorrectly says the software count cache flush is enabled.
The root of the problem is that we are trying to handle all
combinations of options. But we know now that we only expect to see
the software count cache flush enabled if the other options are false.
So split the two cases, which simplifies the logic and fixes the bug.
We were also missing a space before "(hardware accelerated)".
The result is we see one of:
Mitigation: Indirect branch serialisation (kernel only)
Mitigation: Indirect branch cache disabled
Mitigation: Software count cache flush
Mitigation: Software count cache flush (hardware accelerated)
Fixes: ee13cb249fab ("powerpc/64s: Add support for software count cache flush")
Cc: stable(a)vger.kernel.org # v4.19+
Signed-off-by: Michael Ellerman <mpe(a)ellerman.id.au>
Reviewed-by: Michael Neuling <mikey(a)neuling.org>
Reviewed-by: Diana Craciun <diana.craciun(a)nxp.com>
Signed-off-by: Michael Ellerman <mpe(a)ellerman.id.au>
diff --git a/arch/powerpc/kernel/security.c b/arch/powerpc/kernel/security.c
index 9b8631533e02..b33bafb8fcea 100644
--- a/arch/powerpc/kernel/security.c
+++ b/arch/powerpc/kernel/security.c
@@ -190,29 +190,22 @@ ssize_t cpu_show_spectre_v2(struct device *dev, struct device_attribute *attr, c
bcs = security_ftr_enabled(SEC_FTR_BCCTRL_SERIALISED);
ccd = security_ftr_enabled(SEC_FTR_COUNT_CACHE_DISABLED);
- if (bcs || ccd || count_cache_flush_type != COUNT_CACHE_FLUSH_NONE) {
- bool comma = false;
+ if (bcs || ccd) {
seq_buf_printf(&s, "Mitigation: ");
- if (bcs) {
+ if (bcs)
seq_buf_printf(&s, "Indirect branch serialisation (kernel only)");
- comma = true;
- }
- if (ccd) {
- if (comma)
- seq_buf_printf(&s, ", ");
- seq_buf_printf(&s, "Indirect branch cache disabled");
- comma = true;
- }
-
- if (comma)
+ if (bcs && ccd)
seq_buf_printf(&s, ", ");
- seq_buf_printf(&s, "Software count cache flush");
+ if (ccd)
+ seq_buf_printf(&s, "Indirect branch cache disabled");
+ } else if (count_cache_flush_type != COUNT_CACHE_FLUSH_NONE) {
+ seq_buf_printf(&s, "Mitigation: Software count cache flush");
if (count_cache_flush_type == COUNT_CACHE_FLUSH_HW)
- seq_buf_printf(&s, "(hardware accelerated)");
+ seq_buf_printf(&s, " (hardware accelerated)");
} else if (btb_flush_enabled) {
seq_buf_printf(&s, "Mitigation: Branch predictor state flush");
} else {
The patch below does not apply to the 3.18-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(a)vger.kernel.org>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From b5b4453e7912f056da1ca7572574cada32ecb60c Mon Sep 17 00:00:00 2001
From: Michael Ellerman <mpe(a)ellerman.id.au>
Date: Thu, 14 Mar 2019 00:14:38 +1100
Subject: [PATCH] powerpc/vdso64: Fix CLOCK_MONOTONIC inconsistencies across
Y2038
Jakub Drnec reported:
Setting the realtime clock can sometimes make the monotonic clock go
back by over a hundred years. Decreasing the realtime clock across
the y2k38 threshold is one reliable way to reproduce. Allegedly this
can also happen just by running ntpd, I have not managed to
reproduce that other than booting with rtc at >2038 and then running
ntp. When this happens, anything with timers (e.g. openjdk) breaks
rather badly.
And included a test case (slightly edited for brevity):
#define _POSIX_C_SOURCE 199309L
#include <stdio.h>
#include <time.h>
#include <stdlib.h>
#include <unistd.h>
long get_time(void) {
struct timespec tp;
clock_gettime(CLOCK_MONOTONIC, &tp);
return tp.tv_sec + tp.tv_nsec / 1000000000;
}
int main(void) {
long last = get_time();
while(1) {
long now = get_time();
if (now < last) {
printf("clock went backwards by %ld seconds!\n", last - now);
}
last = now;
sleep(1);
}
return 0;
}
Which when run concurrently with:
# date -s 2040-1-1
# date -s 2037-1-1
Will detect the clock going backward.
The root cause is that wtom_clock_sec in struct vdso_data is only a
32-bit signed value, even though we set its value to be equal to
tk->wall_to_monotonic.tv_sec which is 64-bits.
Because the monotonic clock starts at zero when the system boots the
wall_to_montonic.tv_sec offset is negative for current and future
dates. Currently on a freshly booted system the offset will be in the
vicinity of negative 1.5 billion seconds.
However if the wall clock is set past the Y2038 boundary, the offset
from wall to monotonic becomes less than negative 2^31, and no longer
fits in 32-bits. When that value is assigned to wtom_clock_sec it is
truncated and becomes positive, causing the VDSO assembly code to
calculate CLOCK_MONOTONIC incorrectly.
That causes CLOCK_MONOTONIC to jump ahead by ~4 billion seconds which
it is not meant to do. Worse, if the time is then set back before the
Y2038 boundary CLOCK_MONOTONIC will jump backward.
We can fix it simply by storing the full 64-bit offset in the
vdso_data, and using that in the VDSO assembly code. We also shuffle
some of the fields in vdso_data to avoid creating a hole.
The original commit that added the CLOCK_MONOTONIC support to the VDSO
did actually use a 64-bit value for wtom_clock_sec, see commit
a7f290dad32e ("[PATCH] powerpc: Merge vdso's and add vdso support to
32 bits kernel") (Nov 2005). However just 3 days later it was
converted to 32-bits in commit 0c37ec2aa88b ("[PATCH] powerpc: vdso
fixes (take #2)"), and the bug has existed since then AFAICS.
Fixes: 0c37ec2aa88b ("[PATCH] powerpc: vdso fixes (take #2)")
Cc: stable(a)vger.kernel.org # v2.6.15+
Link: http://lkml.kernel.org/r/HaC.ZfES.62bwlnvAvMP.1STMMj@seznam.cz
Reported-by: Jakub Drnec <jaydee(a)email.cz>
Signed-off-by: Michael Ellerman <mpe(a)ellerman.id.au>
diff --git a/arch/powerpc/include/asm/vdso_datapage.h b/arch/powerpc/include/asm/vdso_datapage.h
index 1afe90ade595..bbc06bd72b1f 100644
--- a/arch/powerpc/include/asm/vdso_datapage.h
+++ b/arch/powerpc/include/asm/vdso_datapage.h
@@ -82,10 +82,10 @@ struct vdso_data {
__u32 icache_block_size; /* L1 i-cache block size */
__u32 dcache_log_block_size; /* L1 d-cache log block size */
__u32 icache_log_block_size; /* L1 i-cache log block size */
- __s32 wtom_clock_sec; /* Wall to monotonic clock */
- __s32 wtom_clock_nsec;
- struct timespec stamp_xtime; /* xtime as at tb_orig_stamp */
- __u32 stamp_sec_fraction; /* fractional seconds of stamp_xtime */
+ __u32 stamp_sec_fraction; /* fractional seconds of stamp_xtime */
+ __s32 wtom_clock_nsec; /* Wall to monotonic clock nsec */
+ __s64 wtom_clock_sec; /* Wall to monotonic clock sec */
+ struct timespec stamp_xtime; /* xtime as at tb_orig_stamp */
__u32 syscall_map_64[SYSCALL_MAP_SIZE]; /* map of syscalls */
__u32 syscall_map_32[SYSCALL_MAP_SIZE]; /* map of syscalls */
};
diff --git a/arch/powerpc/kernel/vdso64/gettimeofday.S b/arch/powerpc/kernel/vdso64/gettimeofday.S
index a4ed9edfd5f0..1f324c28705b 100644
--- a/arch/powerpc/kernel/vdso64/gettimeofday.S
+++ b/arch/powerpc/kernel/vdso64/gettimeofday.S
@@ -92,7 +92,7 @@ V_FUNCTION_BEGIN(__kernel_clock_gettime)
* At this point, r4,r5 contain our sec/nsec values.
*/
- lwa r6,WTOM_CLOCK_SEC(r3)
+ ld r6,WTOM_CLOCK_SEC(r3)
lwa r9,WTOM_CLOCK_NSEC(r3)
/* We now have our result in r6,r9. We create a fake dependency
@@ -125,7 +125,7 @@ V_FUNCTION_BEGIN(__kernel_clock_gettime)
bne cr6,75f
/* CLOCK_MONOTONIC_COARSE */
- lwa r6,WTOM_CLOCK_SEC(r3)
+ ld r6,WTOM_CLOCK_SEC(r3)
lwa r9,WTOM_CLOCK_NSEC(r3)
/* check if counter has updated */
The patch below does not apply to the 4.4-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(a)vger.kernel.org>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From b5b4453e7912f056da1ca7572574cada32ecb60c Mon Sep 17 00:00:00 2001
From: Michael Ellerman <mpe(a)ellerman.id.au>
Date: Thu, 14 Mar 2019 00:14:38 +1100
Subject: [PATCH] powerpc/vdso64: Fix CLOCK_MONOTONIC inconsistencies across
Y2038
Jakub Drnec reported:
Setting the realtime clock can sometimes make the monotonic clock go
back by over a hundred years. Decreasing the realtime clock across
the y2k38 threshold is one reliable way to reproduce. Allegedly this
can also happen just by running ntpd, I have not managed to
reproduce that other than booting with rtc at >2038 and then running
ntp. When this happens, anything with timers (e.g. openjdk) breaks
rather badly.
And included a test case (slightly edited for brevity):
#define _POSIX_C_SOURCE 199309L
#include <stdio.h>
#include <time.h>
#include <stdlib.h>
#include <unistd.h>
long get_time(void) {
struct timespec tp;
clock_gettime(CLOCK_MONOTONIC, &tp);
return tp.tv_sec + tp.tv_nsec / 1000000000;
}
int main(void) {
long last = get_time();
while(1) {
long now = get_time();
if (now < last) {
printf("clock went backwards by %ld seconds!\n", last - now);
}
last = now;
sleep(1);
}
return 0;
}
Which when run concurrently with:
# date -s 2040-1-1
# date -s 2037-1-1
Will detect the clock going backward.
The root cause is that wtom_clock_sec in struct vdso_data is only a
32-bit signed value, even though we set its value to be equal to
tk->wall_to_monotonic.tv_sec which is 64-bits.
Because the monotonic clock starts at zero when the system boots the
wall_to_montonic.tv_sec offset is negative for current and future
dates. Currently on a freshly booted system the offset will be in the
vicinity of negative 1.5 billion seconds.
However if the wall clock is set past the Y2038 boundary, the offset
from wall to monotonic becomes less than negative 2^31, and no longer
fits in 32-bits. When that value is assigned to wtom_clock_sec it is
truncated and becomes positive, causing the VDSO assembly code to
calculate CLOCK_MONOTONIC incorrectly.
That causes CLOCK_MONOTONIC to jump ahead by ~4 billion seconds which
it is not meant to do. Worse, if the time is then set back before the
Y2038 boundary CLOCK_MONOTONIC will jump backward.
We can fix it simply by storing the full 64-bit offset in the
vdso_data, and using that in the VDSO assembly code. We also shuffle
some of the fields in vdso_data to avoid creating a hole.
The original commit that added the CLOCK_MONOTONIC support to the VDSO
did actually use a 64-bit value for wtom_clock_sec, see commit
a7f290dad32e ("[PATCH] powerpc: Merge vdso's and add vdso support to
32 bits kernel") (Nov 2005). However just 3 days later it was
converted to 32-bits in commit 0c37ec2aa88b ("[PATCH] powerpc: vdso
fixes (take #2)"), and the bug has existed since then AFAICS.
Fixes: 0c37ec2aa88b ("[PATCH] powerpc: vdso fixes (take #2)")
Cc: stable(a)vger.kernel.org # v2.6.15+
Link: http://lkml.kernel.org/r/HaC.ZfES.62bwlnvAvMP.1STMMj@seznam.cz
Reported-by: Jakub Drnec <jaydee(a)email.cz>
Signed-off-by: Michael Ellerman <mpe(a)ellerman.id.au>
diff --git a/arch/powerpc/include/asm/vdso_datapage.h b/arch/powerpc/include/asm/vdso_datapage.h
index 1afe90ade595..bbc06bd72b1f 100644
--- a/arch/powerpc/include/asm/vdso_datapage.h
+++ b/arch/powerpc/include/asm/vdso_datapage.h
@@ -82,10 +82,10 @@ struct vdso_data {
__u32 icache_block_size; /* L1 i-cache block size */
__u32 dcache_log_block_size; /* L1 d-cache log block size */
__u32 icache_log_block_size; /* L1 i-cache log block size */
- __s32 wtom_clock_sec; /* Wall to monotonic clock */
- __s32 wtom_clock_nsec;
- struct timespec stamp_xtime; /* xtime as at tb_orig_stamp */
- __u32 stamp_sec_fraction; /* fractional seconds of stamp_xtime */
+ __u32 stamp_sec_fraction; /* fractional seconds of stamp_xtime */
+ __s32 wtom_clock_nsec; /* Wall to monotonic clock nsec */
+ __s64 wtom_clock_sec; /* Wall to monotonic clock sec */
+ struct timespec stamp_xtime; /* xtime as at tb_orig_stamp */
__u32 syscall_map_64[SYSCALL_MAP_SIZE]; /* map of syscalls */
__u32 syscall_map_32[SYSCALL_MAP_SIZE]; /* map of syscalls */
};
diff --git a/arch/powerpc/kernel/vdso64/gettimeofday.S b/arch/powerpc/kernel/vdso64/gettimeofday.S
index a4ed9edfd5f0..1f324c28705b 100644
--- a/arch/powerpc/kernel/vdso64/gettimeofday.S
+++ b/arch/powerpc/kernel/vdso64/gettimeofday.S
@@ -92,7 +92,7 @@ V_FUNCTION_BEGIN(__kernel_clock_gettime)
* At this point, r4,r5 contain our sec/nsec values.
*/
- lwa r6,WTOM_CLOCK_SEC(r3)
+ ld r6,WTOM_CLOCK_SEC(r3)
lwa r9,WTOM_CLOCK_NSEC(r3)
/* We now have our result in r6,r9. We create a fake dependency
@@ -125,7 +125,7 @@ V_FUNCTION_BEGIN(__kernel_clock_gettime)
bne cr6,75f
/* CLOCK_MONOTONIC_COARSE */
- lwa r6,WTOM_CLOCK_SEC(r3)
+ ld r6,WTOM_CLOCK_SEC(r3)
lwa r9,WTOM_CLOCK_NSEC(r3)
/* check if counter has updated */