This is a note to let you know that I've just added the patch titled
sched/deadline: Use the revised wakeup rule for suspending constrained dl tasks
to the 4.9-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:
sched-deadline-use-the-revised-wakeup-rule-for-suspending-constrained-dl-tasks.patch
and it can be found in the queue-4.9 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 foo@baz Mon Apr 9 17:09:24 CEST 2018
From: Daniel Bristot de Oliveira <bristot(a)redhat.com>
Date: Mon, 29 May 2017 16:24:03 +0200
Subject: sched/deadline: Use the revised wakeup rule for suspending constrained dl tasks
From: Daniel Bristot de Oliveira <bristot(a)redhat.com>
[ Upstream commit 3effcb4247e74a51f5d8b775a1ee4abf87cc089a ]
We have been facing some problems with self-suspending constrained
deadline tasks. The main reason is that the original CBS was not
designed for such sort of tasks.
One problem reported by Xunlei Pang takes place when a task
suspends, and then is awakened before the deadline, but so close
to the deadline that its remaining runtime can cause the task
to have an absolute density higher than allowed. In such situation,
the original CBS assumes that the task is facing an early activation,
and so it replenishes the task and set another deadline, one deadline
in the future. This rule works fine for implicit deadline tasks.
Moreover, it allows the system to adapt the period of a task in which
the external event source suffered from a clock drift.
However, this opens the window for bandwidth leakage for constrained
deadline tasks. For instance, a task with the following parameters:
runtime = 5 ms
deadline = 7 ms
[density] = 5 / 7 = 0.71
period = 1000 ms
If the task runs for 1 ms, and then suspends for another 1ms,
it will be awakened with the following parameters:
remaining runtime = 4
laxity = 5
presenting a absolute density of 4 / 5 = 0.80.
In this case, the original CBS would assume the task had an early
wakeup. Then, CBS will reset the runtime, and the absolute deadline will
be postponed by one relative deadline, allowing the task to run.
The problem is that, if the task runs this pattern forever, it will keep
receiving bandwidth, being able to run 1ms every 2ms. Following this
behavior, the task would be able to run 500 ms in 1 sec. Thus running
more than the 5 ms / 1 sec the admission control allowed it to run.
Trying to address the self-suspending case, Luca Abeni, Giuseppe
Lipari, and Juri Lelli [1] revisited the CBS in order to deal with
self-suspending tasks. In the new approach, rather than
replenishing/postponing the absolute deadline, the revised wakeup rule
adjusts the remaining runtime, reducing it to fit into the allowed
density.
A revised version of the idea is:
At a given time t, the maximum absolute density of a task cannot be
higher than its relative density, that is:
runtime / (deadline - t) <= dl_runtime / dl_deadline
Knowing the laxity of a task (deadline - t), it is possible to move
it to the other side of the equality, thus enabling to define max
remaining runtime a task can use within the absolute deadline, without
over-running the allowed density:
runtime = (dl_runtime / dl_deadline) * (deadline - t)
For instance, in our previous example, the task could still run:
runtime = ( 5 / 7 ) * 5
runtime = 3.57 ms
Without causing damage for other deadline tasks. It is note worthy
that the laxity cannot be negative because that would cause a negative
runtime. Thus, this patch depends on the patch:
df8eac8cafce ("sched/deadline: Throttle a constrained deadline task activated after the deadline")
Which throttles a constrained deadline task activated after the
deadline.
Finally, it is also possible to use the revised wakeup rule for
all other tasks, but that would require some more discussions
about pros and cons.
Reported-by: Xunlei Pang <xpang(a)redhat.com>
Signed-off-by: Daniel Bristot de Oliveira <bristot(a)redhat.com>
[peterz: replaced dl_is_constrained with dl_is_implicit]
Signed-off-by: Peter Zijlstra (Intel) <peterz(a)infradead.org>
Cc: Juri Lelli <juri.lelli(a)arm.com>
Cc: Linus Torvalds <torvalds(a)linux-foundation.org>
Cc: Luca Abeni <luca.abeni(a)santannapisa.it>
Cc: Mike Galbraith <efault(a)gmx.de>
Cc: Peter Zijlstra <peterz(a)infradead.org>
Cc: Romulo Silva de Oliveira <romulo.deoliveira(a)ufsc.br>
Cc: Steven Rostedt <rostedt(a)goodmis.org>
Cc: Thomas Gleixner <tglx(a)linutronix.de>
Cc: Tommaso Cucinotta <tommaso.cucinotta(a)sssup.it>
Link: http://lkml.kernel.org/r/5c800ab3a74a168a84ee5f3f84d12a02e11383be.149580380…
Signed-off-by: Ingo Molnar <mingo(a)kernel.org>
Signed-off-by: Sasha Levin <alexander.levin(a)microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
include/linux/sched.h | 1
kernel/sched/core.c | 2
kernel/sched/deadline.c | 98 ++++++++++++++++++++++++++++++++++++++++++------
3 files changed, 89 insertions(+), 12 deletions(-)
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -1412,6 +1412,7 @@ struct sched_dl_entity {
u64 dl_deadline; /* relative deadline of each instance */
u64 dl_period; /* separation of two instances (period) */
u64 dl_bw; /* dl_runtime / dl_deadline */
+ u64 dl_density; /* dl_runtime / dl_deadline */
/*
* Actual scheduling parameters. Initialized with the values above,
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -2184,6 +2184,7 @@ void __dl_clear_params(struct task_struc
dl_se->dl_period = 0;
dl_se->flags = 0;
dl_se->dl_bw = 0;
+ dl_se->dl_density = 0;
dl_se->dl_throttled = 0;
dl_se->dl_yielded = 0;
@@ -3912,6 +3913,7 @@ __setparam_dl(struct task_struct *p, con
dl_se->dl_period = attr->sched_period ?: dl_se->dl_deadline;
dl_se->flags = attr->sched_flags;
dl_se->dl_bw = to_ratio(dl_se->dl_period, dl_se->dl_runtime);
+ dl_se->dl_density = to_ratio(dl_se->dl_deadline, dl_se->dl_runtime);
/*
* Changing the parameters of a task is 'tricky' and we're not doing
--- a/kernel/sched/deadline.c
+++ b/kernel/sched/deadline.c
@@ -484,13 +484,84 @@ static bool dl_entity_overflow(struct sc
}
/*
- * When a -deadline entity is queued back on the runqueue, its runtime and
- * deadline might need updating.
+ * Revised wakeup rule [1]: For self-suspending tasks, rather then
+ * re-initializing task's runtime and deadline, the revised wakeup
+ * rule adjusts the task's runtime to avoid the task to overrun its
+ * density.
*
- * The policy here is that we update the deadline of the entity only if:
- * - the current deadline is in the past,
- * - using the remaining runtime with the current deadline would make
- * the entity exceed its bandwidth.
+ * Reasoning: a task may overrun the density if:
+ * runtime / (deadline - t) > dl_runtime / dl_deadline
+ *
+ * Therefore, runtime can be adjusted to:
+ * runtime = (dl_runtime / dl_deadline) * (deadline - t)
+ *
+ * In such way that runtime will be equal to the maximum density
+ * the task can use without breaking any rule.
+ *
+ * [1] Luca Abeni, Giuseppe Lipari, and Juri Lelli. 2015. Constant
+ * bandwidth server revisited. SIGBED Rev. 11, 4 (January 2015), 19-24.
+ */
+static void
+update_dl_revised_wakeup(struct sched_dl_entity *dl_se, struct rq *rq)
+{
+ u64 laxity = dl_se->deadline - rq_clock(rq);
+
+ /*
+ * If the task has deadline < period, and the deadline is in the past,
+ * it should already be throttled before this check.
+ *
+ * See update_dl_entity() comments for further details.
+ */
+ WARN_ON(dl_time_before(dl_se->deadline, rq_clock(rq)));
+
+ dl_se->runtime = (dl_se->dl_density * laxity) >> 20;
+}
+
+/*
+ * Regarding the deadline, a task with implicit deadline has a relative
+ * deadline == relative period. A task with constrained deadline has a
+ * relative deadline <= relative period.
+ *
+ * We support constrained deadline tasks. However, there are some restrictions
+ * applied only for tasks which do not have an implicit deadline. See
+ * update_dl_entity() to know more about such restrictions.
+ *
+ * The dl_is_implicit() returns true if the task has an implicit deadline.
+ */
+static inline bool dl_is_implicit(struct sched_dl_entity *dl_se)
+{
+ return dl_se->dl_deadline == dl_se->dl_period;
+}
+
+/*
+ * When a deadline entity is placed in the runqueue, its runtime and deadline
+ * might need to be updated. This is done by a CBS wake up rule. There are two
+ * different rules: 1) the original CBS; and 2) the Revisited CBS.
+ *
+ * When the task is starting a new period, the Original CBS is used. In this
+ * case, the runtime is replenished and a new absolute deadline is set.
+ *
+ * When a task is queued before the begin of the next period, using the
+ * remaining runtime and deadline could make the entity to overflow, see
+ * dl_entity_overflow() to find more about runtime overflow. When such case
+ * is detected, the runtime and deadline need to be updated.
+ *
+ * If the task has an implicit deadline, i.e., deadline == period, the Original
+ * CBS is applied. the runtime is replenished and a new absolute deadline is
+ * set, as in the previous cases.
+ *
+ * However, the Original CBS does not work properly for tasks with
+ * deadline < period, which are said to have a constrained deadline. By
+ * applying the Original CBS, a constrained deadline task would be able to run
+ * runtime/deadline in a period. With deadline < period, the task would
+ * overrun the runtime/period allowed bandwidth, breaking the admission test.
+ *
+ * In order to prevent this misbehave, the Revisited CBS is used for
+ * constrained deadline tasks when a runtime overflow is detected. In the
+ * Revisited CBS, rather than replenishing & setting a new absolute deadline,
+ * the remaining runtime of the task is reduced to avoid runtime overflow.
+ * Please refer to the comments update_dl_revised_wakeup() function to find
+ * more about the Revised CBS rule.
*/
static void update_dl_entity(struct sched_dl_entity *dl_se,
struct sched_dl_entity *pi_se)
@@ -500,6 +571,14 @@ static void update_dl_entity(struct sche
if (dl_time_before(dl_se->deadline, rq_clock(rq)) ||
dl_entity_overflow(dl_se, pi_se, rq_clock(rq))) {
+
+ if (unlikely(!dl_is_implicit(dl_se) &&
+ !dl_time_before(dl_se->deadline, rq_clock(rq)) &&
+ !dl_se->dl_boosted)){
+ update_dl_revised_wakeup(dl_se, rq);
+ return;
+ }
+
dl_se->deadline = rq_clock(rq) + pi_se->dl_deadline;
dl_se->runtime = pi_se->dl_runtime;
}
@@ -961,11 +1040,6 @@ static void dequeue_dl_entity(struct sch
__dequeue_dl_entity(dl_se);
}
-static inline bool dl_is_constrained(struct sched_dl_entity *dl_se)
-{
- return dl_se->dl_deadline < dl_se->dl_period;
-}
-
static void enqueue_task_dl(struct rq *rq, struct task_struct *p, int flags)
{
struct task_struct *pi_task = rt_mutex_get_top_task(p);
@@ -997,7 +1071,7 @@ static void enqueue_task_dl(struct rq *r
* If that is the case, the task will be throttled and
* the replenishment timer will be set to the next period.
*/
- if (!p->dl.dl_throttled && dl_is_constrained(&p->dl))
+ if (!p->dl.dl_throttled && !dl_is_implicit(&p->dl))
dl_check_constrained_dl(&p->dl);
/*
Patches currently in stable-queue which might be from bristot(a)redhat.com are
queue-4.9/sched-deadline-use-the-revised-wakeup-rule-for-suspending-constrained-dl-tasks.patch
This is a note to let you know that I've just added the patch titled
s390: move _text symbol to address higher than zero
to the 4.9-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:
s390-move-_text-symbol-to-address-higher-than-zero.patch
and it can be found in the queue-4.9 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 foo@baz Mon Apr 9 17:09:24 CEST 2018
From: Heiko Carstens <heiko.carstens(a)de.ibm.com>
Date: Thu, 4 May 2017 09:42:22 +0200
Subject: s390: move _text symbol to address higher than zero
From: Heiko Carstens <heiko.carstens(a)de.ibm.com>
[ Upstream commit d04a4c76f71dd5335f8e499b59617382d84e2b8d ]
The perf tool assumes that kernel symbols are never present at address
zero. In fact it assumes if functions that map symbols to addresses
return zero, that the symbol was not found.
Given that s390's _text symbol historically is located at address zero
this yields at least a couple of false errors and warnings in one of
perf's test cases about not present symbols ("perf test 1").
To fix this simply move the _text symbol to address 0x200, just behind
the initial psw and channel program located at the beginning of the
kernel image. This is now hard coded within the linker script.
I tried a nicer solution which moves the initial psw and channel
program into an own section. However that would move the symbols
within the "real" head.text section to different addresses, since the
".org" statements within head.S are relative to the head.text
section. If there is a new section in front, everything else will be
moved. Alternatively I could have adjusted all ".org" statements. But
this current solution seems to be the easiest one, since nobody really
cares where the _text symbol is actually located.
Reported-by: Zvonko Kosic <zkosic(a)linux.vnet.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens(a)de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky(a)de.ibm.com>
Signed-off-by: Sasha Levin <alexander.levin(a)microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
arch/s390/kernel/vmlinux.lds.S | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)
--- a/arch/s390/kernel/vmlinux.lds.S
+++ b/arch/s390/kernel/vmlinux.lds.S
@@ -31,8 +31,14 @@ SECTIONS
{
. = 0x00000000;
.text : {
- _text = .; /* Text and read-only data */
+ /* Text and read-only data */
HEAD_TEXT
+ /*
+ * E.g. perf doesn't like symbols starting at address zero,
+ * therefore skip the initial PSW and channel program located
+ * at address zero and let _text start at 0x200.
+ */
+ _text = 0x200;
TEXT_TEXT
SCHED_TEXT
CPUIDLE_TEXT
Patches currently in stable-queue which might be from heiko.carstens(a)de.ibm.com are
queue-4.9/s390-move-_text-symbol-to-address-higher-than-zero.patch
This is a note to let you know that I've just added the patch titled
rtc: snvs: fix an incorrect check of return value
to the 4.9-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:
rtc-snvs-fix-an-incorrect-check-of-return-value.patch
and it can be found in the queue-4.9 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 foo@baz Mon Apr 9 17:09:24 CEST 2018
From: Pan Bian <bianpan2016(a)163.com>
Date: Sun, 23 Apr 2017 13:43:24 +0800
Subject: rtc: snvs: fix an incorrect check of return value
From: Pan Bian <bianpan2016(a)163.com>
[ Upstream commit 758929005f06f954b7e1c87a1c9fdb44157b228f ]
Function devm_regmap_init_mmio() returns an ERR_PTR on error. However,
in function snvs_rtc_probe() its return value is checked against NULL.
This patch fixes it by checking the return value with IS_ERR().
Signed-off-by: Pan Bian <bianpan2016(a)163.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni(a)free-electrons.com>
Signed-off-by: Sasha Levin <alexander.levin(a)microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
drivers/rtc/rtc-snvs.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/drivers/rtc/rtc-snvs.c
+++ b/drivers/rtc/rtc-snvs.c
@@ -257,7 +257,7 @@ static int snvs_rtc_probe(struct platfor
of_property_read_u32(pdev->dev.of_node, "offset", &data->offset);
}
- if (!data->regmap) {
+ if (IS_ERR(data->regmap)) {
dev_err(&pdev->dev, "Can't find snvs syscon\n");
return -ENODEV;
}
Patches currently in stable-queue which might be from bianpan2016(a)163.com are
queue-4.9/cx25840-fix-unchecked-return-values.patch
queue-4.9/usb-dwc3-keystone-check-return-value.patch
queue-4.9/rtc-snvs-fix-an-incorrect-check-of-return-value.patch
This is a note to let you know that I've just added the patch titled
s390/dasd: fix hanging safe offline
to the 4.9-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:
s390-dasd-fix-hanging-safe-offline.patch
and it can be found in the queue-4.9 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 foo@baz Mon Apr 9 17:09:24 CEST 2018
From: Stefan Haberland <sth(a)linux.vnet.ibm.com>
Date: Thu, 18 May 2017 13:24:45 +0200
Subject: s390/dasd: fix hanging safe offline
From: Stefan Haberland <sth(a)linux.vnet.ibm.com>
[ Upstream commit e8ac01555d9e464249e8bb122337d6d6e5589ccc ]
The safe offline processing may hang forever because it waits for I/O
which can not be started because of the offline flag that prevents new
I/O from being started.
Allow I/O to be started during safe offline processing because in this
special case we take care that the queues are empty before throwing away
the device.
Signed-off-by: Stefan Haberland <sth(a)linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky(a)de.ibm.com>
Signed-off-by: Sasha Levin <alexander.levin(a)microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
drivers/s390/block/dasd.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)
--- a/drivers/s390/block/dasd.c
+++ b/drivers/s390/block/dasd.c
@@ -1950,8 +1950,12 @@ static int __dasd_device_is_unusable(str
{
int mask = ~(DASD_STOPPED_DC_WAIT | DASD_UNRESUMED_PM);
- if (test_bit(DASD_FLAG_OFFLINE, &device->flags)) {
- /* dasd is being set offline. */
+ if (test_bit(DASD_FLAG_OFFLINE, &device->flags) &&
+ !test_bit(DASD_FLAG_SAFE_OFFLINE_RUNNING, &device->flags)) {
+ /*
+ * dasd is being set offline
+ * but it is no safe offline where we have to allow I/O
+ */
return 1;
}
if (device->stopped) {
Patches currently in stable-queue which might be from sth(a)linux.vnet.ibm.com are
queue-4.9/s390-dasd-fix-hanging-safe-offline.patch
This is a note to let you know that I've just added the patch titled
rtc: opal: Handle disabled TPO in opal_get_tpo_time()
to the 4.9-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:
rtc-opal-handle-disabled-tpo-in-opal_get_tpo_time.patch
and it can be found in the queue-4.9 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 foo@baz Mon Apr 9 17:09:24 CEST 2018
From: Vaibhav Jain <vaibhav(a)linux.vnet.ibm.com>
Date: Fri, 19 May 2017 15:35:09 +0530
Subject: rtc: opal: Handle disabled TPO in opal_get_tpo_time()
From: Vaibhav Jain <vaibhav(a)linux.vnet.ibm.com>
[ Upstream commit 6dc1cf6f932bb0ea4d8f5e913a0a401ecacd2f03 ]
On PowerNV platform when Timed-Power-On(TPO) is disabled, read of
stored TPO yields value with all date components set to '0' inside
opal_get_tpo_time(). The function opal_to_tm() then converts it to an
offset from year 1900 yielding alarm-time == "1900-00-01
00:00:00". This causes problems with __rtc_read_alarm() that
expecting an offset from "1970-00-01 00:00:00" and returned alarm-time
results in a -ve value for time64_t. Which ultimately results in this
error reported in kernel logs with a seemingly garbage value:
"rtc rtc0: invalid alarm value: -2-1--1041528741
2005511117:71582844:32"
We fix this by explicitly handling the case of all alarm date-time
components being '0' inside opal_get_tpo_time() and returning -ENOENT
in such a case. This signals generic rtc that no alarm is set and it
bails out from the alarm initialization flow without reporting the
above error.
Signed-off-by: Vaibhav Jain <vaibhav(a)linux.vnet.ibm.com>
Reported-by: Steve Best <sbest(a)redhat.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni(a)free-electrons.com>
Signed-off-by: Sasha Levin <alexander.levin(a)microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
drivers/rtc/rtc-opal.c | 10 ++++++++++
1 file changed, 10 insertions(+)
--- a/drivers/rtc/rtc-opal.c
+++ b/drivers/rtc/rtc-opal.c
@@ -150,6 +150,16 @@ static int opal_get_tpo_time(struct devi
y_m_d = be32_to_cpu(__y_m_d);
h_m_s_ms = ((u64)be32_to_cpu(__h_m) << 32);
+
+ /* check if no alarm is set */
+ if (y_m_d == 0 && h_m_s_ms == 0) {
+ pr_debug("No alarm is set\n");
+ rc = -ENOENT;
+ goto exit;
+ } else {
+ pr_debug("Alarm set to %x %llx\n", y_m_d, h_m_s_ms);
+ }
+
opal_to_tm(y_m_d, h_m_s_ms, &alarm->time);
exit:
Patches currently in stable-queue which might be from vaibhav(a)linux.vnet.ibm.com are
queue-4.9/rtc-interface-validate-alarm-time-before-handling-rollover.patch
queue-4.9/rtc-opal-handle-disabled-tpo-in-opal_get_tpo_time.patch
This is a note to let you know that I've just added the patch titled
rtc: interface: Validate alarm-time before handling rollover
to the 4.9-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:
rtc-interface-validate-alarm-time-before-handling-rollover.patch
and it can be found in the queue-4.9 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 foo@baz Mon Apr 9 17:09:24 CEST 2018
From: Vaibhav Jain <vaibhav(a)linux.vnet.ibm.com>
Date: Fri, 19 May 2017 22:18:55 +0530
Subject: rtc: interface: Validate alarm-time before handling rollover
From: Vaibhav Jain <vaibhav(a)linux.vnet.ibm.com>
[ Upstream commit da96aea0ed177105cb13ee83b328f6c61e061d3f ]
In function __rtc_read_alarm() its possible for an alarm time-stamp to
be invalid even after replacing missing components with current
time-stamp. The condition 'alarm->time.tm_year < 70' will trigger this
case and will cause the call to 'rtc_tm_to_time64(&alarm->time)'
return a negative value for variable t_alm.
While handling alarm rollover this negative t_alm (assumed to seconds
offset from '1970-01-01 00:00:00') is converted back to rtc_time via
rtc_time64_to_tm() which results in this error log with seemingly
garbage values:
"rtc rtc0: invalid alarm value: -2-1--1041528741
2005511117:71582844:32"
This error was generated when the rtc driver (rtc-opal in this case)
returned an alarm time-stamp of '00-00-00 00:00:00' to indicate that
the alarm is disabled. Though I have submitted a separate fix for the
rtc-opal driver, this issue may potentially impact other
existing/future rtc drivers.
To fix this issue the patch validates the alarm time-stamp just after
filling up the missing datetime components and if rtc_valid_tm() still
reports it to be invalid then bails out of the function without
handling the rollover.
Reported-by: Steve Best <sbest(a)redhat.com>
Signed-off-by: Vaibhav Jain <vaibhav(a)linux.vnet.ibm.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni(a)free-electrons.com>
Signed-off-by: Sasha Levin <alexander.levin(a)microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
drivers/rtc/interface.c | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)
--- a/drivers/rtc/interface.c
+++ b/drivers/rtc/interface.c
@@ -227,6 +227,13 @@ int __rtc_read_alarm(struct rtc_device *
missing = year;
}
+ /* Can't proceed if alarm is still invalid after replacing
+ * missing fields.
+ */
+ err = rtc_valid_tm(&alarm->time);
+ if (err)
+ goto done;
+
/* with luck, no rollover is needed */
t_now = rtc_tm_to_time64(&now);
t_alm = rtc_tm_to_time64(&alarm->time);
@@ -278,9 +285,9 @@ int __rtc_read_alarm(struct rtc_device *
dev_warn(&rtc->dev, "alarm rollover not handled\n");
}
-done:
err = rtc_valid_tm(&alarm->time);
+done:
if (err) {
dev_warn(&rtc->dev, "invalid alarm value: %d-%d-%d %d:%d:%d\n",
alarm->time.tm_year + 1900, alarm->time.tm_mon + 1,
Patches currently in stable-queue which might be from vaibhav(a)linux.vnet.ibm.com are
queue-4.9/rtc-interface-validate-alarm-time-before-handling-rollover.patch
queue-4.9/rtc-opal-handle-disabled-tpo-in-opal_get_tpo_time.patch
This is a note to let you know that I've just added the patch titled
rtc: m41t80: fix SQW dividers override when setting a date
to the 4.9-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:
rtc-m41t80-fix-sqw-dividers-override-when-setting-a-date.patch
and it can be found in the queue-4.9 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 foo@baz Mon Apr 9 17:09:24 CEST 2018
From: Gary Bisson <gary.bisson(a)boundarydevices.com>
Date: Tue, 25 Apr 2017 16:45:15 +0200
Subject: rtc: m41t80: fix SQW dividers override when setting a date
From: Gary Bisson <gary.bisson(a)boundarydevices.com>
[ Upstream commit 0f546b058b86ea2f661cc7a6e931cee5a29959ef ]
This patch is only relevant for RTC with the SQ_ALT feature which
means the clock output frequency divider is stored in the weekday
register.
Current implementation discards the previous dividers value and clear
them as soon as the time is set.
Signed-off-by: Gary Bisson <gary.bisson(a)boundarydevices.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni(a)free-electrons.com>
Signed-off-by: Sasha Levin <alexander.levin(a)microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
drivers/rtc/rtc-m41t80.c | 12 ++++++++++++
1 file changed, 12 insertions(+)
--- a/drivers/rtc/rtc-m41t80.c
+++ b/drivers/rtc/rtc-m41t80.c
@@ -168,6 +168,7 @@ static int m41t80_get_datetime(struct i2
/* Sets the given date and time to the real time clock. */
static int m41t80_set_datetime(struct i2c_client *client, struct rtc_time *tm)
{
+ struct m41t80_data *clientdata = i2c_get_clientdata(client);
unsigned char buf[8];
int err, flags;
@@ -183,6 +184,17 @@ static int m41t80_set_datetime(struct i2
buf[M41T80_REG_YEAR] = bin2bcd(tm->tm_year - 100);
buf[M41T80_REG_WDAY] = tm->tm_wday;
+ /* If the square wave output is controlled in the weekday register */
+ if (clientdata->features & M41T80_FEATURE_SQ_ALT) {
+ int val;
+
+ val = i2c_smbus_read_byte_data(client, M41T80_REG_WDAY);
+ if (val < 0)
+ return val;
+
+ buf[M41T80_REG_WDAY] |= (val & 0xf0);
+ }
+
err = i2c_smbus_write_i2c_block_data(client, M41T80_REG_SSEC,
sizeof(buf), buf);
if (err < 0) {
Patches currently in stable-queue which might be from gary.bisson(a)boundarydevices.com are
queue-4.9/rtc-m41t80-fix-sqw-dividers-override-when-setting-a-date.patch
This is a note to let you know that I've just added the patch titled
rt2x00: do not pause queue unconditionally on error path
to the 4.9-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:
rt2x00-do-not-pause-queue-unconditionally-on-error-path.patch
and it can be found in the queue-4.9 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 foo@baz Mon Apr 9 17:09:24 CEST 2018
From: Stanislaw Gruszka <sgruszka(a)redhat.com>
Date: Tue, 19 Dec 2017 12:33:56 +0100
Subject: rt2x00: do not pause queue unconditionally on error path
From: Stanislaw Gruszka <sgruszka(a)redhat.com>
[ Upstream commit 6dd80efd75ce7c2dbd9f117cf585ee2b33a42ee1 ]
Pausing queue without checking threshold is racy with txdone path.
Moreover we do not need pause queue on any error, but only if queue
is full - in case when we send RTS frame ( other cases of almost full
queue are already handled in rt2x00queue_write_tx_frame() ).
Patch fixes of theoretically possible problem of pausing empty
queue.
Signed-off-by: Stanislaw Gruszka <sgruszka(a)redhat.com>
Tested-by: Enrico Mioso <mrkiko.rs(a)gmail.com>
Signed-off-by: Kalle Valo <kvalo(a)codeaurora.org>
Signed-off-by: Sasha Levin <alexander.levin(a)microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
drivers/net/wireless/ralink/rt2x00/rt2x00mac.c | 22 ++++++++++++++--------
1 file changed, 14 insertions(+), 8 deletions(-)
--- a/drivers/net/wireless/ralink/rt2x00/rt2x00mac.c
+++ b/drivers/net/wireless/ralink/rt2x00/rt2x00mac.c
@@ -142,15 +142,25 @@ void rt2x00mac_tx(struct ieee80211_hw *h
if (!rt2x00dev->ops->hw->set_rts_threshold &&
(tx_info->control.rates[0].flags & (IEEE80211_TX_RC_USE_RTS_CTS |
IEEE80211_TX_RC_USE_CTS_PROTECT))) {
- if (rt2x00queue_available(queue) <= 1)
- goto exit_fail;
+ if (rt2x00queue_available(queue) <= 1) {
+ /*
+ * Recheck for full queue under lock to avoid race
+ * conditions with rt2x00lib_txdone().
+ */
+ spin_lock(&queue->tx_lock);
+ if (rt2x00queue_threshold(queue))
+ rt2x00queue_pause_queue(queue);
+ spin_unlock(&queue->tx_lock);
+
+ goto exit_free_skb;
+ }
if (rt2x00mac_tx_rts_cts(rt2x00dev, queue, skb))
- goto exit_fail;
+ goto exit_free_skb;
}
if (unlikely(rt2x00queue_write_tx_frame(queue, skb, control->sta, false)))
- goto exit_fail;
+ goto exit_free_skb;
/*
* Pausing queue has to be serialized with rt2x00lib_txdone(). Note
@@ -164,10 +174,6 @@ void rt2x00mac_tx(struct ieee80211_hw *h
return;
- exit_fail:
- spin_lock(&queue->tx_lock);
- rt2x00queue_pause_queue(queue);
- spin_unlock(&queue->tx_lock);
exit_free_skb:
ieee80211_free_txskb(hw, skb);
}
Patches currently in stable-queue which might be from sgruszka(a)redhat.com are
queue-4.9/rt2x00-do-not-pause-queue-unconditionally-on-error-path.patch
This is a note to let you know that I've just added the patch titled
rds; Reset rs->rs_bound_addr in rds_add_bound() failure path
to the 4.9-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:
rds-reset-rs-rs_bound_addr-in-rds_add_bound-failure-path.patch
and it can be found in the queue-4.9 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 foo@baz Mon Apr 9 17:09:24 CEST 2018
From: Sowmini Varadhan <sowmini.varadhan(a)oracle.com>
Date: Fri, 22 Dec 2017 09:38:59 -0800
Subject: rds; Reset rs->rs_bound_addr in rds_add_bound() failure path
From: Sowmini Varadhan <sowmini.varadhan(a)oracle.com>
[ Upstream commit 7ae0c649c47f1c5d2db8cee6dd75855970af1669 ]
If the rds_sock is not added to the bind_hash_table, we must
reset rs_bound_addr so that rds_remove_bound will not trip on
this rds_sock.
rds_add_bound() does a rds_sock_put() in this failure path, so
failing to reset rs_bound_addr will result in a socket refcount
bug, and will trigger a WARN_ON with the stack shown below when
the application subsequently tries to close the PF_RDS socket.
WARNING: CPU: 20 PID: 19499 at net/rds/af_rds.c:496 \
rds_sock_destruct+0x15/0x30 [rds]
:
__sk_destruct+0x21/0x190
rds_remove_bound.part.13+0xb6/0x140 [rds]
rds_release+0x71/0x120 [rds]
sock_release+0x1a/0x70
sock_close+0xe/0x20
__fput+0xd5/0x210
task_work_run+0x82/0xa0
do_exit+0x2ce/0xb30
? syscall_trace_enter+0x1cc/0x2b0
do_group_exit+0x39/0xa0
SyS_exit_group+0x10/0x10
do_syscall_64+0x61/0x1a0
Signed-off-by: Sowmini Varadhan <sowmini.varadhan(a)oracle.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar(a)oracle.com>
Signed-off-by: David S. Miller <davem(a)davemloft.net>
Signed-off-by: Sasha Levin <alexander.levin(a)microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
net/rds/bind.c | 1 +
1 file changed, 1 insertion(+)
--- a/net/rds/bind.c
+++ b/net/rds/bind.c
@@ -114,6 +114,7 @@ static int rds_add_bound(struct rds_sock
rs, &addr, (int)ntohs(*port));
break;
} else {
+ rs->rs_bound_addr = 0;
rds_sock_put(rs);
ret = -ENOMEM;
break;
Patches currently in stable-queue which might be from sowmini.varadhan(a)oracle.com are
queue-4.9/rds-reset-rs-rs_bound_addr-in-rds_add_bound-failure-path.patch
This is a note to let you know that I've just added the patch titled
RDMA/iw_cxgb4: Avoid touch after free error in ARP failure handlers
to the 4.9-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:
rdma-iw_cxgb4-avoid-touch-after-free-error-in-arp-failure-handlers.patch
and it can be found in the queue-4.9 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 foo@baz Mon Apr 9 17:09:24 CEST 2018
From: Raju Rangoju <rajur(a)chelsio.com>
Date: Mon, 15 May 2017 06:40:39 +0000
Subject: RDMA/iw_cxgb4: Avoid touch after free error in ARP failure handlers
From: Raju Rangoju <rajur(a)chelsio.com>
[ Upstream commit 1dad0ebeea1cd890b8892523f736916e245b0aef ]
The patch 761e19a504af (RDMA/iw_cxgb4: Handle return value of
c4iw_ofld_send() in abort_arp_failure()) from May 6, 2016
leads to the following static checker warning:
drivers/infiniband/hw/cxgb4/cm.c:575 abort_arp_failure()
warn: passing freed memory 'skb'
Also fixes skb leak when l2t resolution fails
Fixes: 761e19a504afa55 (RDMA/iw_cxgb4: Handle return value of
c4iw_ofld_send() in abort_arp_failure())
Reported-by: Dan Carpenter <dan.carpenter(a)oracle.com>
Cc: Dan Carpenter <dan.carpenter(a)oracle.com>
Signed-off-by: Raju Rangoju <rajur(a)chelsio.com>
Reviewed-by: Steve Wise <swise(a)opengridcomputing.com>
Signed-off-by: Doug Ledford <dledford(a)redhat.com>
Signed-off-by: Sasha Levin <alexander.levin(a)microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
drivers/infiniband/hw/cxgb4/cm.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)
--- a/drivers/infiniband/hw/cxgb4/cm.c
+++ b/drivers/infiniband/hw/cxgb4/cm.c
@@ -488,6 +488,7 @@ static int _put_ep_safe(struct c4iw_dev
ep = *((struct c4iw_ep **)(skb->cb + 2 * sizeof(void *)));
release_ep_resources(ep);
+ kfree_skb(skb);
return 0;
}
@@ -498,6 +499,7 @@ static int _put_pass_ep_safe(struct c4iw
ep = *((struct c4iw_ep **)(skb->cb + 2 * sizeof(void *)));
c4iw_put_ep(&ep->parent_ep->com);
release_ep_resources(ep);
+ kfree_skb(skb);
return 0;
}
@@ -569,11 +571,13 @@ static void abort_arp_failure(void *hand
PDBG("%s rdev %p\n", __func__, rdev);
req->cmd = CPL_ABORT_NO_RST;
+ skb_get(skb);
ret = c4iw_ofld_send(rdev, skb);
if (ret) {
__state_set(&ep->com, DEAD);
queue_arp_failure_cpl(ep, skb, FAKE_CPL_PUT_EP_SAFE);
- }
+ } else
+ kfree_skb(skb);
}
static int send_flowc(struct c4iw_ep *ep)
Patches currently in stable-queue which might be from rajur(a)chelsio.com are
queue-4.9/rdma-iw_cxgb4-avoid-touch-after-free-error-in-arp-failure-handlers.patch