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 d61a5c1063515e855bedb1b81e20e50b0ac3541e Mon Sep 17 00:00:00 2001
From: Lukas Wunner <lukas(a)wunner.de>
Date: Sun, 11 Feb 2018 10:38:28 +0100
Subject: [PATCH] drm/nouveau: Fix deadlock on runtime suspend
nouveau's ->runtime_suspend hook calls drm_kms_helper_poll_disable(),
which waits for the output poll worker to finish if it's running.
The output poll worker meanwhile calls pm_runtime_get_sync() in
nouveau_connector_detect() which waits for the ongoing suspend to finish,
causing a deadlock.
Fix by not acquiring a runtime PM ref if nouveau_connector_detect() is
called in the output poll worker's context. This is safe because
the poll worker is only enabled while runtime active and we know that
->runtime_suspend waits for it to finish.
Other contexts calling nouveau_connector_detect() do require a runtime
PM ref, these comprise:
status_store() drm sysfs interface
->fill_modes drm callback
drm_fb_helper_probe_connector_modes()
drm_mode_getconnector()
nouveau_connector_hotplug()
nouveau_display_hpd_work()
nv17_tv_set_property()
Stack trace for posterity:
INFO: task kworker/0:1:58 blocked for more than 120 seconds.
Workqueue: events output_poll_execute [drm_kms_helper]
Call Trace:
schedule+0x28/0x80
rpm_resume+0x107/0x6e0
__pm_runtime_resume+0x47/0x70
nouveau_connector_detect+0x7e/0x4a0 [nouveau]
nouveau_connector_detect_lvds+0x132/0x180 [nouveau]
drm_helper_probe_detect_ctx+0x85/0xd0 [drm_kms_helper]
output_poll_execute+0x11e/0x1c0 [drm_kms_helper]
process_one_work+0x184/0x380
worker_thread+0x2e/0x390
INFO: task kworker/0:2:252 blocked for more than 120 seconds.
Workqueue: pm pm_runtime_work
Call Trace:
schedule+0x28/0x80
schedule_timeout+0x1e3/0x370
wait_for_completion+0x123/0x190
flush_work+0x142/0x1c0
nouveau_pmops_runtime_suspend+0x7e/0xd0 [nouveau]
pci_pm_runtime_suspend+0x5c/0x180
vga_switcheroo_runtime_suspend+0x1e/0xa0
__rpm_callback+0xc1/0x200
rpm_callback+0x1f/0x70
rpm_suspend+0x13c/0x640
pm_runtime_work+0x6e/0x90
process_one_work+0x184/0x380
worker_thread+0x2e/0x390
Bugzilla: https://bugs.archlinux.org/task/53497
Bugzilla: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=870523
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=70388#c33
Fixes: 5addcf0a5f0f ("nouveau: add runtime PM support (v0.9)")
Cc: stable(a)vger.kernel.org # v3.12+: 27d4ee03078a: workqueue: Allow retrieval of current task's work struct
Cc: stable(a)vger.kernel.org # v3.12+: 25c058ccaf2e: drm: Allow determining if current task is output poll worker
Cc: Ben Skeggs <bskeggs(a)redhat.com>
Cc: Dave Airlie <airlied(a)redhat.com>
Reviewed-by: Lyude Paul <lyude(a)redhat.com>
Signed-off-by: Lukas Wunner <lukas(a)wunner.de>
Link: https://patchwork.freedesktop.org/patch/msgid/b7d2cbb609a80f59ccabfdf479b9d…
diff --git a/drivers/gpu/drm/nouveau/nouveau_connector.c b/drivers/gpu/drm/nouveau/nouveau_connector.c
index 69d6e61a01ec..6ed9cb053dfa 100644
--- a/drivers/gpu/drm/nouveau/nouveau_connector.c
+++ b/drivers/gpu/drm/nouveau/nouveau_connector.c
@@ -570,9 +570,15 @@ nouveau_connector_detect(struct drm_connector *connector, bool force)
nv_connector->edid = NULL;
}
- ret = pm_runtime_get_sync(connector->dev->dev);
- if (ret < 0 && ret != -EACCES)
- return conn_status;
+ /* Outputs are only polled while runtime active, so acquiring a
+ * runtime PM ref here is unnecessary (and would deadlock upon
+ * runtime suspend because it waits for polling to finish).
+ */
+ if (!drm_kms_helper_is_poll_worker()) {
+ ret = pm_runtime_get_sync(connector->dev->dev);
+ if (ret < 0 && ret != -EACCES)
+ return conn_status;
+ }
nv_encoder = nouveau_connector_ddc_detect(connector);
if (nv_encoder && (i2c = nv_encoder->i2c) != NULL) {
@@ -647,8 +653,10 @@ nouveau_connector_detect(struct drm_connector *connector, bool force)
out:
- pm_runtime_mark_last_busy(connector->dev->dev);
- pm_runtime_put_autosuspend(connector->dev->dev);
+ if (!drm_kms_helper_is_poll_worker()) {
+ pm_runtime_mark_last_busy(connector->dev->dev);
+ pm_runtime_put_autosuspend(connector->dev->dev);
+ }
return conn_status;
}
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 d61a5c1063515e855bedb1b81e20e50b0ac3541e Mon Sep 17 00:00:00 2001
From: Lukas Wunner <lukas(a)wunner.de>
Date: Sun, 11 Feb 2018 10:38:28 +0100
Subject: [PATCH] drm/nouveau: Fix deadlock on runtime suspend
nouveau's ->runtime_suspend hook calls drm_kms_helper_poll_disable(),
which waits for the output poll worker to finish if it's running.
The output poll worker meanwhile calls pm_runtime_get_sync() in
nouveau_connector_detect() which waits for the ongoing suspend to finish,
causing a deadlock.
Fix by not acquiring a runtime PM ref if nouveau_connector_detect() is
called in the output poll worker's context. This is safe because
the poll worker is only enabled while runtime active and we know that
->runtime_suspend waits for it to finish.
Other contexts calling nouveau_connector_detect() do require a runtime
PM ref, these comprise:
status_store() drm sysfs interface
->fill_modes drm callback
drm_fb_helper_probe_connector_modes()
drm_mode_getconnector()
nouveau_connector_hotplug()
nouveau_display_hpd_work()
nv17_tv_set_property()
Stack trace for posterity:
INFO: task kworker/0:1:58 blocked for more than 120 seconds.
Workqueue: events output_poll_execute [drm_kms_helper]
Call Trace:
schedule+0x28/0x80
rpm_resume+0x107/0x6e0
__pm_runtime_resume+0x47/0x70
nouveau_connector_detect+0x7e/0x4a0 [nouveau]
nouveau_connector_detect_lvds+0x132/0x180 [nouveau]
drm_helper_probe_detect_ctx+0x85/0xd0 [drm_kms_helper]
output_poll_execute+0x11e/0x1c0 [drm_kms_helper]
process_one_work+0x184/0x380
worker_thread+0x2e/0x390
INFO: task kworker/0:2:252 blocked for more than 120 seconds.
Workqueue: pm pm_runtime_work
Call Trace:
schedule+0x28/0x80
schedule_timeout+0x1e3/0x370
wait_for_completion+0x123/0x190
flush_work+0x142/0x1c0
nouveau_pmops_runtime_suspend+0x7e/0xd0 [nouveau]
pci_pm_runtime_suspend+0x5c/0x180
vga_switcheroo_runtime_suspend+0x1e/0xa0
__rpm_callback+0xc1/0x200
rpm_callback+0x1f/0x70
rpm_suspend+0x13c/0x640
pm_runtime_work+0x6e/0x90
process_one_work+0x184/0x380
worker_thread+0x2e/0x390
Bugzilla: https://bugs.archlinux.org/task/53497
Bugzilla: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=870523
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=70388#c33
Fixes: 5addcf0a5f0f ("nouveau: add runtime PM support (v0.9)")
Cc: stable(a)vger.kernel.org # v3.12+: 27d4ee03078a: workqueue: Allow retrieval of current task's work struct
Cc: stable(a)vger.kernel.org # v3.12+: 25c058ccaf2e: drm: Allow determining if current task is output poll worker
Cc: Ben Skeggs <bskeggs(a)redhat.com>
Cc: Dave Airlie <airlied(a)redhat.com>
Reviewed-by: Lyude Paul <lyude(a)redhat.com>
Signed-off-by: Lukas Wunner <lukas(a)wunner.de>
Link: https://patchwork.freedesktop.org/patch/msgid/b7d2cbb609a80f59ccabfdf479b9d…
diff --git a/drivers/gpu/drm/nouveau/nouveau_connector.c b/drivers/gpu/drm/nouveau/nouveau_connector.c
index 69d6e61a01ec..6ed9cb053dfa 100644
--- a/drivers/gpu/drm/nouveau/nouveau_connector.c
+++ b/drivers/gpu/drm/nouveau/nouveau_connector.c
@@ -570,9 +570,15 @@ nouveau_connector_detect(struct drm_connector *connector, bool force)
nv_connector->edid = NULL;
}
- ret = pm_runtime_get_sync(connector->dev->dev);
- if (ret < 0 && ret != -EACCES)
- return conn_status;
+ /* Outputs are only polled while runtime active, so acquiring a
+ * runtime PM ref here is unnecessary (and would deadlock upon
+ * runtime suspend because it waits for polling to finish).
+ */
+ if (!drm_kms_helper_is_poll_worker()) {
+ ret = pm_runtime_get_sync(connector->dev->dev);
+ if (ret < 0 && ret != -EACCES)
+ return conn_status;
+ }
nv_encoder = nouveau_connector_ddc_detect(connector);
if (nv_encoder && (i2c = nv_encoder->i2c) != NULL) {
@@ -647,8 +653,10 @@ nouveau_connector_detect(struct drm_connector *connector, bool force)
out:
- pm_runtime_mark_last_busy(connector->dev->dev);
- pm_runtime_put_autosuspend(connector->dev->dev);
+ if (!drm_kms_helper_is_poll_worker()) {
+ pm_runtime_mark_last_busy(connector->dev->dev);
+ pm_runtime_put_autosuspend(connector->dev->dev);
+ }
return conn_status;
}
This is a note to let you know that I've just added the patch titled
x86/oprofile: Fix bogus GCC-8 warning in nmi_setup()
to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
x86-oprofile-fix-bogus-gcc-8-warning-in-nmi_setup.patch
and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From 85c615eb52222bc5fab6c7190d146bc59fac289e Mon Sep 17 00:00:00 2001
From: Arnd Bergmann <arnd(a)arndb.de>
Date: Tue, 20 Feb 2018 21:58:21 +0100
Subject: x86/oprofile: Fix bogus GCC-8 warning in nmi_setup()
From: Arnd Bergmann <arnd(a)arndb.de>
commit 85c615eb52222bc5fab6c7190d146bc59fac289e upstream.
GCC-8 shows a warning for the x86 oprofile code that copies per-CPU
data from CPU 0 to all other CPUs, which when building a non-SMP
kernel turns into a memcpy() with identical source and destination
pointers:
arch/x86/oprofile/nmi_int.c: In function 'mux_clone':
arch/x86/oprofile/nmi_int.c:285:2: error: 'memcpy' source argument is the same as destination [-Werror=restrict]
memcpy(per_cpu(cpu_msrs, cpu).multiplex,
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
per_cpu(cpu_msrs, 0).multiplex,
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
sizeof(struct op_msr) * model->num_virt_counters);
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
arch/x86/oprofile/nmi_int.c: In function 'nmi_setup':
arch/x86/oprofile/nmi_int.c:466:3: error: 'memcpy' source argument is the same as destination [-Werror=restrict]
arch/x86/oprofile/nmi_int.c:470:3: error: 'memcpy' source argument is the same as destination [-Werror=restrict]
I have analyzed a number of such warnings now: some are valid and the
GCC warning is welcome. Others turned out to be false-positives, and
GCC was changed to not warn about those any more. This is a corner case
that is a false-positive but the GCC developers feel it's better to keep
warning about it.
In this case, it seems best to work around it by telling GCC
a little more clearly that this code path is never hit with
an IS_ENABLED() configuration check.
Cc:stable as we also want old kernels to build cleanly with GCC-8.
Signed-off-by: Arnd Bergmann <arnd(a)arndb.de>
Cc: Jessica Yu <jeyu(a)kernel.org>
Cc: Kees Cook <keescook(a)chromium.org>
Cc: Linus Torvalds <torvalds(a)linux-foundation.org>
Cc: Martin Sebor <msebor(a)gcc.gnu.org>
Cc: Peter Zijlstra <peterz(a)infradead.org>
Cc: Robert Richter <rric(a)kernel.org>
Cc: Thomas Gleixner <tglx(a)linutronix.de>
Cc: oprofile-list(a)lists.sf.net
Cc: stable(a)vger.kernel.org
Link: http://lkml.kernel.org/r/20180220205826.2008875-1-arnd@arndb.de
Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84095
Signed-off-by: Ingo Molnar <mingo(a)kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
arch/x86/oprofile/nmi_int.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/arch/x86/oprofile/nmi_int.c
+++ b/arch/x86/oprofile/nmi_int.c
@@ -471,7 +471,7 @@ static int nmi_setup(void)
goto fail;
for_each_possible_cpu(cpu) {
- if (!cpu)
+ if (!IS_ENABLED(CONFIG_SMP) || !cpu)
continue;
memcpy(per_cpu(cpu_msrs, cpu).counters,
Patches currently in stable-queue which might be from arnd(a)arndb.de are
queue-4.4/x86-oprofile-fix-bogus-gcc-8-warning-in-nmi_setup.patch
queue-4.4/cfg80211-fix-cfg80211_beacon_dup.patch
This is a note to let you know that I've just added the patch titled
usb: renesas_usbhs: missed the "running" flag in usb_dmac with rx path
to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
usb-renesas_usbhs-missed-the-running-flag-in-usb_dmac-with-rx-path.patch
and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From 17aa31f13cad25daa19d3f923323f552e87bc874 Mon Sep 17 00:00:00 2001
From: Yoshihiro Shimoda <yoshihiro.shimoda.uh(a)renesas.com>
Date: Mon, 5 Feb 2018 17:12:35 +0900
Subject: usb: renesas_usbhs: missed the "running" flag in usb_dmac with rx path
From: Yoshihiro Shimoda <yoshihiro.shimoda.uh(a)renesas.com>
commit 17aa31f13cad25daa19d3f923323f552e87bc874 upstream.
This fixes an issue that a gadget driver (usb_f_fs) is possible to
stop rx transactions after the usb-dmac is used because the following
functions missed to set/check the "running" flag.
- usbhsf_dma_prepare_pop_with_usb_dmac()
- usbhsf_dma_pop_done_with_usb_dmac()
So, if next transaction uses pio, the usbhsf_prepare_pop() can not
start the transaction because the "running" flag is 0.
Fixes: 8355b2b3082d ("usb: renesas_usbhs: fix the behavior of some usbhs_pkt_handle")
Cc: <stable(a)vger.kernel.org> # v3.19+
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh(a)renesas.com>
Signed-off-by: Felipe Balbi <felipe.balbi(a)linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
drivers/usb/renesas_usbhs/fifo.c | 5 +++++
1 file changed, 5 insertions(+)
--- a/drivers/usb/renesas_usbhs/fifo.c
+++ b/drivers/usb/renesas_usbhs/fifo.c
@@ -999,6 +999,10 @@ static int usbhsf_dma_prepare_pop_with_u
if ((uintptr_t)pkt->buf & (USBHS_USB_DMAC_XFER_SIZE - 1))
goto usbhsf_pio_prepare_pop;
+ /* return at this time if the pipe is running */
+ if (usbhs_pipe_is_running(pipe))
+ return 0;
+
usbhs_pipe_config_change_bfre(pipe, 1);
ret = usbhsf_fifo_select(pipe, fifo, 0);
@@ -1189,6 +1193,7 @@ static int usbhsf_dma_pop_done_with_usb_
usbhsf_fifo_clear(pipe, fifo);
pkt->actual = usbhs_dma_calc_received_size(pkt, chan, rcv_len);
+ usbhs_pipe_running(pipe, 0);
usbhsf_dma_stop(pipe, fifo);
usbhsf_dma_unmap(pkt);
usbhsf_fifo_unselect(pipe, pipe->fifo);
Patches currently in stable-queue which might be from yoshihiro.shimoda.uh(a)renesas.com are
queue-4.4/usb-renesas_usbhs-missed-the-running-flag-in-usb_dmac-with-rx-path.patch
This is a note to let you know that I've just added the patch titled
usb: ohci: Proper handling of ed_rm_list to handle race condition between usb_kill_urb() and finish_unlinks()
to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
usb-ohci-proper-handling-of-ed_rm_list-to-handle-race-condition-between-usb_kill_urb-and-finish_unlinks.patch
and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From 46408ea558df13b110e0866b99624384a33bdeba Mon Sep 17 00:00:00 2001
From: AMAN DEEP <aman.deep(a)samsung.com>
Date: Thu, 8 Feb 2018 11:55:01 +0800
Subject: usb: ohci: Proper handling of ed_rm_list to handle race condition between usb_kill_urb() and finish_unlinks()
From: AMAN DEEP <aman.deep(a)samsung.com>
commit 46408ea558df13b110e0866b99624384a33bdeba upstream.
There is a race condition between finish_unlinks->finish_urb() function
and usb_kill_urb() in ohci controller case. The finish_urb calls
spin_unlock(&ohci->lock) before usb_hcd_giveback_urb() function call,
then if during this time, usb_kill_urb is called for another endpoint,
then new ed will be added to ed_rm_list at beginning for unlink, and
ed_rm_list will point to newly added.
When finish_urb() is completed in finish_unlinks() and ed->td_list
becomes empty as in below code (in finish_unlinks() function):
if (list_empty(&ed->td_list)) {
*last = ed->ed_next;
ed->ed_next = NULL;
} else if (ohci->rh_state == OHCI_RH_RUNNING) {
*last = ed->ed_next;
ed->ed_next = NULL;
ed_schedule(ohci, ed);
}
The *last = ed->ed_next will make ed_rm_list to point to ed->ed_next
and previously added ed by usb_kill_urb will be left unreferenced by
ed_rm_list. This causes usb_kill_urb() hang forever waiting for
finish_unlink to remove added ed from ed_rm_list.
The main reason for hang in this race condtion is addition and removal
of ed from ed_rm_list in the beginning during usb_kill_urb and later
last* is modified in finish_unlinks().
As suggested by Alan Stern, the solution for proper handling of
ohci->ed_rm_list is to remove ed from the ed_rm_list before finishing
any URBs. Then at the end, we can add ed back to the list if necessary.
This properly handle the updated ohci->ed_rm_list in usb_kill_urb().
Fixes: 977dcfdc6031 ("USB: OHCI: don't lose track of EDs when a controller dies")
Acked-by: Alan Stern <stern(a)rowland.harvard.edu>
CC: <stable(a)vger.kernel.org>
Signed-off-by: Aman Deep <aman.deep(a)samsung.com>
Signed-off-by: Jeffy Chen <jeffy.chen(a)rock-chips.com>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
drivers/usb/host/ohci-q.c | 17 ++++++++++-------
1 file changed, 10 insertions(+), 7 deletions(-)
--- a/drivers/usb/host/ohci-q.c
+++ b/drivers/usb/host/ohci-q.c
@@ -1018,6 +1018,8 @@ skip_ed:
* have modified this list. normally it's just prepending
* entries (which we'd ignore), but paranoia won't hurt.
*/
+ *last = ed->ed_next;
+ ed->ed_next = NULL;
modified = 0;
/* unlink urbs as requested, but rescan the list after
@@ -1076,21 +1078,22 @@ rescan_this:
goto rescan_this;
/*
- * If no TDs are queued, take ED off the ed_rm_list.
+ * If no TDs are queued, ED is now idle.
* Otherwise, if the HC is running, reschedule.
- * If not, leave it on the list for further dequeues.
+ * If the HC isn't running, add ED back to the
+ * start of the list for later processing.
*/
if (list_empty(&ed->td_list)) {
- *last = ed->ed_next;
- ed->ed_next = NULL;
ed->state = ED_IDLE;
list_del(&ed->in_use_list);
} else if (ohci->rh_state == OHCI_RH_RUNNING) {
- *last = ed->ed_next;
- ed->ed_next = NULL;
ed_schedule(ohci, ed);
} else {
- last = &ed->ed_next;
+ ed->ed_next = ohci->ed_rm_list;
+ ohci->ed_rm_list = ed;
+ /* Don't loop on the same ED */
+ if (last == &ohci->ed_rm_list)
+ last = &ed->ed_next;
}
if (modified)
Patches currently in stable-queue which might be from aman.deep(a)samsung.com are
queue-4.4/usb-ohci-proper-handling-of-ed_rm_list-to-handle-race-condition-between-usb_kill_urb-and-finish_unlinks.patch