* [PATCH] fuse: freezing abort when use wait_event_killable{,_exclusive}().
@ 2016-12-05 3:19 cuilifei
2016-12-06 22:15 ` Rafael J. Wysocki
0 siblings, 1 reply; 14+ messages in thread
From: cuilifei @ 2016-12-05 3:19 UTC (permalink / raw)
To: linux-kernel
Cc: miklos, rjw, pavel, len.brown, linux-fsdevel, viro, piaoyingmin,
liucai, cuilifei
Freezing process can abort when a client is waiting uninterruptibly
for a response. Add new macro wait_fatal_freezable to try to fix it.
Signed-off-by: cuilifei <cuilifei@xiaomi.com>
---
fs/fuse/dev.c | 30 ++++++++++++++++++++++++++----
include/linux/freezer.h | 26 ++++++++++++++++++++++++++
2 files changed, 52 insertions(+), 4 deletions(-)
diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c
index 70ea57c..e33a081 100644
--- a/fs/fuse/dev.c
+++ b/fs/fuse/dev.c
@@ -19,6 +19,7 @@
#include <linux/pipe_fs_i.h>
#include <linux/swap.h>
#include <linux/splice.h>
+#include <linux/freezer.h>
MODULE_ALIAS_MISCDEV(FUSE_MINOR);
MODULE_ALIAS("devname:fuse");
@@ -99,6 +100,19 @@ void fuse_request_free(struct fuse_req *req)
kmem_cache_free(fuse_req_cachep, req);
}
+static void block_sigs(sigset_t *oldset)
+{
+ sigset_t mask;
+
+ siginitsetinv(&mask, sigmask(SIGKILL));
+ sigprocmask(SIG_BLOCK, &mask, oldset);
+}
+
+static void restore_sigs(sigset_t *oldset)
+{
+ sigprocmask(SIG_SETMASK, oldset, NULL);
+}
+
void __fuse_get_request(struct fuse_req *req)
{
atomic_inc(&req->count);
@@ -134,13 +148,18 @@ static struct fuse_req *__fuse_get_req(struct fuse_conn *fc, unsigned npages,
bool for_background)
{
struct fuse_req *req;
+ sigset_t oldset;
+ int intr;
int err;
atomic_inc(&fc->num_waiting);
if (fuse_block_alloc(fc, for_background)) {
err = -EINTR;
- if (wait_event_killable_exclusive(fc->blocked_waitq,
- !fuse_block_alloc(fc, for_background)))
+ block_sigs(&oldset);
+ intr = wait_fatal_freezable(fc->blocked_waitq,
+ !fuse_block_alloc(fc, for_background), true);
+ restore_sigs(&oldset);
+ if (intr)
goto out;
}
/* Matches smp_wmb() in fuse_set_initialized() */
@@ -427,9 +446,12 @@ static void request_wait_answer(struct fuse_conn *fc, struct fuse_req *req)
}
if (!test_bit(FR_FORCE, &req->flags)) {
+ sigset_t oldset;
/* Only fatal signals may interrupt this */
- err = wait_event_killable(req->waitq,
- test_bit(FR_FINISHED, &req->flags));
+ block_sigs(&oldset);
+ err = wait_fatal_freezable(req->waitq,
+ test_bit(FR_FINISHED, &req->flags), false);
+ restore_sigs(&oldset);
if (!err)
return;
diff --git a/include/linux/freezer.h b/include/linux/freezer.h
index dd03e83..2504cd0 100644
--- a/include/linux/freezer.h
+++ b/include/linux/freezer.h
@@ -256,6 +256,22 @@ static inline int freezable_schedule_hrtimeout_range(ktime_t *expires,
__retval; \
})
+#define wait_fatal_freezable(wq, condition, exclusive) \
+({ \
+ int __ret = 0; \
+ do { \
+ if (exclusive) \
+ __ret = wait_event_interruptible_exclusive(wq, \
+ condition); \
+ else \
+ __ret = wait_event_interruptible(wq, \
+ condition); \
+ if (!__ret || fatal_signal_pending(current)) \
+ break; \
+ } while (try_to_freeze()); \
+ __ret; \
+})
+
#else /* !CONFIG_FREEZER */
static inline bool frozen(struct task_struct *p) { return false; }
static inline bool freezing(struct task_struct *p) { return false; }
@@ -296,6 +312,16 @@ static inline void set_freezable(void) {}
#define wait_event_freezekillable_unsafe(wq, condition) \
wait_event_killable(wq, condition)
+#define wait_fatal_freezable(wq, condition, exclusive) \
+({ \
+ int __ret = 0; \
+ if (exclusive) \
+ __ret = wait_event_killable_exclusive(wq, condition); \
+ else \
+ __ret = wait_event_killable(wq, condition); \
+ __ret; \
+})
+
#endif /* !CONFIG_FREEZER */
#endif /* FREEZER_H_INCLUDED */
--
1.9.1
^ permalink raw reply related [flat|nested] 14+ messages in thread
* Re: [PATCH] fuse: freezing abort when use wait_event_killable{,_exclusive}().
2016-12-05 3:19 [PATCH] fuse: freezing abort when use wait_event_killable{,_exclusive}() cuilifei
@ 2016-12-06 22:15 ` Rafael J. Wysocki
2016-12-08 6:31 ` 答复: " 崔立飞
0 siblings, 1 reply; 14+ messages in thread
From: Rafael J. Wysocki @ 2016-12-06 22:15 UTC (permalink / raw)
To: cuilifei
Cc: linux-kernel, miklos, pavel, len.brown, linux-fsdevel, viro,
piaoyingmin, liucai, Jiri Kosina
On Monday, December 05, 2016 11:19:45 AM cuilifei wrote:
> Freezing process can abort when a client is waiting uninterruptibly
> for a response. Add new macro wait_fatal_freezable to try to fix it.
>
> Signed-off-by: cuilifei <cuilifei@xiaomi.com>
I'm not a big fan of this to be honest.
Do we really want to suspend the system (or freeze tasks for other reasons)
if that happens?
> ---
> fs/fuse/dev.c | 30 ++++++++++++++++++++++++++----
> include/linux/freezer.h | 26 ++++++++++++++++++++++++++
> 2 files changed, 52 insertions(+), 4 deletions(-)
>
> diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c
> index 70ea57c..e33a081 100644
> --- a/fs/fuse/dev.c
> +++ b/fs/fuse/dev.c
> @@ -19,6 +19,7 @@
> #include <linux/pipe_fs_i.h>
> #include <linux/swap.h>
> #include <linux/splice.h>
> +#include <linux/freezer.h>
>
> MODULE_ALIAS_MISCDEV(FUSE_MINOR);
> MODULE_ALIAS("devname:fuse");
> @@ -99,6 +100,19 @@ void fuse_request_free(struct fuse_req *req)
> kmem_cache_free(fuse_req_cachep, req);
> }
>
> +static void block_sigs(sigset_t *oldset)
> +{
> + sigset_t mask;
> +
> + siginitsetinv(&mask, sigmask(SIGKILL));
> + sigprocmask(SIG_BLOCK, &mask, oldset);
> +}
> +
> +static void restore_sigs(sigset_t *oldset)
> +{
> + sigprocmask(SIG_SETMASK, oldset, NULL);
> +}
> +
> void __fuse_get_request(struct fuse_req *req)
> {
> atomic_inc(&req->count);
> @@ -134,13 +148,18 @@ static struct fuse_req *__fuse_get_req(struct fuse_conn *fc, unsigned npages,
> bool for_background)
> {
> struct fuse_req *req;
> + sigset_t oldset;
> + int intr;
> int err;
> atomic_inc(&fc->num_waiting);
>
> if (fuse_block_alloc(fc, for_background)) {
> err = -EINTR;
> - if (wait_event_killable_exclusive(fc->blocked_waitq,
> - !fuse_block_alloc(fc, for_background)))
> + block_sigs(&oldset);
> + intr = wait_fatal_freezable(fc->blocked_waitq,
> + !fuse_block_alloc(fc, for_background), true);
> + restore_sigs(&oldset);
> + if (intr)
> goto out;
> }
> /* Matches smp_wmb() in fuse_set_initialized() */
> @@ -427,9 +446,12 @@ static void request_wait_answer(struct fuse_conn *fc, struct fuse_req *req)
> }
>
> if (!test_bit(FR_FORCE, &req->flags)) {
> + sigset_t oldset;
> /* Only fatal signals may interrupt this */
> - err = wait_event_killable(req->waitq,
> - test_bit(FR_FINISHED, &req->flags));
> + block_sigs(&oldset);
> + err = wait_fatal_freezable(req->waitq,
> + test_bit(FR_FINISHED, &req->flags), false);
> + restore_sigs(&oldset);
> if (!err)
> return;
>
> diff --git a/include/linux/freezer.h b/include/linux/freezer.h
> index dd03e83..2504cd0 100644
> --- a/include/linux/freezer.h
> +++ b/include/linux/freezer.h
> @@ -256,6 +256,22 @@ static inline int freezable_schedule_hrtimeout_range(ktime_t *expires,
> __retval; \
> })
>
> +#define wait_fatal_freezable(wq, condition, exclusive) \
> +({ \
> + int __ret = 0; \
> + do { \
> + if (exclusive) \
> + __ret = wait_event_interruptible_exclusive(wq, \
> + condition); \
> + else \
> + __ret = wait_event_interruptible(wq, \
> + condition); \
> + if (!__ret || fatal_signal_pending(current)) \
> + break; \
> + } while (try_to_freeze()); \
> + __ret; \
> +})
> +
> #else /* !CONFIG_FREEZER */
> static inline bool frozen(struct task_struct *p) { return false; }
> static inline bool freezing(struct task_struct *p) { return false; }
> @@ -296,6 +312,16 @@ static inline void set_freezable(void) {}
> #define wait_event_freezekillable_unsafe(wq, condition) \
> wait_event_killable(wq, condition)
>
> +#define wait_fatal_freezable(wq, condition, exclusive) \
> +({ \
> + int __ret = 0; \
> + if (exclusive) \
> + __ret = wait_event_killable_exclusive(wq, condition); \
> + else \
> + __ret = wait_event_killable(wq, condition); \
> + __ret; \
> +})
> +
> #endif /* !CONFIG_FREEZER */
>
> #endif /* FREEZER_H_INCLUDED */
>
Thanks,
Rafael
^ permalink raw reply [flat|nested] 14+ messages in thread
* 答复: [PATCH] fuse: freezing abort when use wait_event_killable{,_exclusive}().
2016-12-06 22:15 ` Rafael J. Wysocki
@ 2016-12-08 6:31 ` 崔立飞
2016-12-14 10:09 ` 崔立飞
2016-12-16 1:34 ` 崔立飞
0 siblings, 2 replies; 14+ messages in thread
From: 崔立飞 @ 2016-12-08 6:31 UTC (permalink / raw)
To: Rafael J. Wysocki
Cc: linux-kernel, miklos, pavel, len.brown, linux-fsdevel, viro,
朴英敏, 刘才,
Jiri Kosina, 崔立飞
Hi Rafael,
The fuse we used is without the commit "fuse: don't mess with blocking signals" committed by Al Viro.
So we find the issue SIGBUS. In the page fault, trying to read page in fuse is interrupted,
which will lead to SIGBUS issue.
All Android platforms, include Android N, have the SIGUBS issue. All the SIGBUS issues are produced
in the freezing process.
In our Android platform, the root-cause of SIGBUS is :
suspend procedure will set the signal pending flag(TIF_SIGPENDING) and then wake up the task
which is TASK_INTERRUPTIBLE status . The request_wait_answer, which calls wait_event_interruptible,
is interrupted and the fuse request is still in pending status, which leads to SIGBUS sent to caller.
This issue can be reproduced by adding delays in funciton handle_read,
which is in the Android sdcard daemon process.
So we merge the commit "fuse: don't mess with blocking signals", which just use wait_event_killable{,_exclusive}().
It fix the SIGBUS issue. But the freezing will fail, because the freezing procedure cannot wake up the task which
is in TASK_KILLABLE(TASK_WAKEKILL | TASK_UNINTERRUPTIBLE) status. And the suspend procedure will abort
until the time is out.
In this patch, we try to fix the issue mentioned above.
> ---
> fs/fuse/dev.c | 30 ++++++++++++++++++++++++++----
> include/linux/freezer.h | 26 ++++++++++++++++++++++++++
> 2 files changed, 52 insertions(+), 4 deletions(-)
>
> diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c
> index 70ea57c..e33a081 100644
> --- a/fs/fuse/dev.c
> +++ b/fs/fuse/dev.c
> @@ -19,6 +19,7 @@
> #include <linux/pipe_fs_i.h>
> #include <linux/swap.h>
> #include <linux/splice.h>
> +#include <linux/freezer.h>
>
> MODULE_ALIAS_MISCDEV(FUSE_MINOR);
> MODULE_ALIAS("devname:fuse");
> @@ -99,6 +100,19 @@ void fuse_request_free(struct fuse_req *req)
> kmem_cache_free(fuse_req_cachep, req);
> }
>
> +static void block_sigs(sigset_t *oldset)
> +{
> + sigset_t mask;
> +
> + siginitsetinv(&mask, sigmask(SIGKILL));
> + sigprocmask(SIG_BLOCK, &mask, oldset);
> +}
> +
> +static void restore_sigs(sigset_t *oldset)
> +{
> + sigprocmask(SIG_SETMASK, oldset, NULL);
> +}
> +
> void __fuse_get_request(struct fuse_req *req)
> {
> atomic_inc(&req->count);
> @@ -134,13 +148,18 @@ static struct fuse_req *__fuse_get_req(struct fuse_conn *fc, unsigned npages,
> bool for_background)
> {
> struct fuse_req *req;
> + sigset_t oldset;
> + int intr;
> int err;
> atomic_inc(&fc->num_waiting);
>
> if (fuse_block_alloc(fc, for_background)) {
> err = -EINTR;
> - if (wait_event_killable_exclusive(fc->blocked_waitq,
> - !fuse_block_alloc(fc, for_background)))
> + block_sigs(&oldset);
> + intr = wait_fatal_freezable(fc->blocked_waitq,
> + !fuse_block_alloc(fc, for_background), true);
> + restore_sigs(&oldset);
> + if (intr)
> goto out;
> }
> /* Matches smp_wmb() in fuse_set_initialized() */
> @@ -427,9 +446,12 @@ static void request_wait_answer(struct fuse_conn *fc, struct fuse_req *req)
> }
>
> if (!test_bit(FR_FORCE, &req->flags)) {
> + sigset_t oldset;
> /* Only fatal signals may interrupt this */
> - err = wait_event_killable(req->waitq,
> - test_bit(FR_FINISHED, &req->flags));
> + block_sigs(&oldset);
> + err = wait_fatal_freezable(req->waitq,
> + test_bit(FR_FINISHED, &req->flags), false);
> + restore_sigs(&oldset);
> if (!err)
> return;
>
> diff --git a/include/linux/freezer.h b/include/linux/freezer.h
> index dd03e83..2504cd0 100644
> --- a/include/linux/freezer.h
> +++ b/include/linux/freezer.h
> @@ -256,6 +256,22 @@ static inline int freezable_schedule_hrtimeout_range(ktime_t *expires,
> __retval; \
> })
>
> +#define wait_fatal_freezable(wq, condition, exclusive) \
> +({ \
> + int __ret = 0; \
> + do { \
> + if (exclusive) \
> + __ret = wait_event_interruptible_exclusive(wq, \ //set the TASK_INTERRUPTIBLE
> + condition); \ //can be waked up by suspend procedure
> + else \
> + __ret = wait_event_interruptible(wq, \
> + condition); \
> + if (!__ret || fatal_signal_pending(current)) \ //check condition or there is fatal signal
> + break; \ //if true, wait finish
> + } while (try_to_freeze()); \ //if freezing is in effect, try to freeze the task
> + __ret; \
> +})
> +
> #else /* !CONFIG_FREEZER */
> static inline bool frozen(struct task_struct *p) { return false; }
> static inline bool freezing(struct task_struct *p) { return false; }
> @@ -296,6 +312,16 @@ static inline void set_freezable(void) {}
> #define wait_event_freezekillable_unsafe(wq, condition) \
> wait_event_killable(wq, condition)
>
> +#define wait_fatal_freezable(wq, condition, exclusive) \
> +({ \
> + int __ret = 0; \
> + if (exclusive) \
> + __ret = wait_event_killable_exclusive(wq, condition); \
> + else \
> + __ret = wait_event_killable(wq, condition); \
> + __ret; \
> +})
> +
> #endif /* !CONFIG_FREEZER */
>
> #endif /* FREEZER_H_INCLUDED */
>
Thanks.
BR,
________________________________________
发件人: Rafael J. Wysocki <rjw@rjwysocki.net>
发送时间: 2016年12月7日 6:15
收件人: 崔立飞
抄送: linux-kernel@vger.kernel.org; miklos@szeredi.hu; pavel@ucw.cz; len.brown@intel.com; linux-fsdevel@vger.kernel.org; viro@zeniv.linux.org.uk; 朴英敏; 刘才; Jiri Kosina
主题: Re: [PATCH] fuse: freezing abort when use wait_event_killable{,_exclusive}().
On Monday, December 05, 2016 11:19:45 AM cuilifei wrote:
> Freezing process can abort when a client is waiting uninterruptibly
> for a response. Add new macro wait_fatal_freezable to try to fix it.
>
> Signed-off-by: cuilifei <cuilifei@xiaomi.com>
I'm not a big fan of this to be honest.
Do we really want to suspend the system (or freeze tasks for other reasons)
if that happens?
> ---
> fs/fuse/dev.c | 30 ++++++++++++++++++++++++++----
> include/linux/freezer.h | 26 ++++++++++++++++++++++++++
> 2 files changed, 52 insertions(+), 4 deletions(-)
>
> diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c
> index 70ea57c..e33a081 100644
> --- a/fs/fuse/dev.c
> +++ b/fs/fuse/dev.c
> @@ -19,6 +19,7 @@
> #include <linux/pipe_fs_i.h>
> #include <linux/swap.h>
> #include <linux/splice.h>
> +#include <linux/freezer.h>
>
> MODULE_ALIAS_MISCDEV(FUSE_MINOR);
> MODULE_ALIAS("devname:fuse");
> @@ -99,6 +100,19 @@ void fuse_request_free(struct fuse_req *req)
> kmem_cache_free(fuse_req_cachep, req);
> }
>
> +static void block_sigs(sigset_t *oldset)
> +{
> + sigset_t mask;
> +
> + siginitsetinv(&mask, sigmask(SIGKILL));
> + sigprocmask(SIG_BLOCK, &mask, oldset);
> +}
> +
> +static void restore_sigs(sigset_t *oldset)
> +{
> + sigprocmask(SIG_SETMASK, oldset, NULL);
> +}
> +
> void __fuse_get_request(struct fuse_req *req)
> {
> atomic_inc(&req->count);
> @@ -134,13 +148,18 @@ static struct fuse_req *__fuse_get_req(struct fuse_conn *fc, unsigned npages,
> bool for_background)
> {
> struct fuse_req *req;
> + sigset_t oldset;
> + int intr;
> int err;
> atomic_inc(&fc->num_waiting);
>
> if (fuse_block_alloc(fc, for_background)) {
> err = -EINTR;
> - if (wait_event_killable_exclusive(fc->blocked_waitq,
> - !fuse_block_alloc(fc, for_background)))
> + block_sigs(&oldset);
> + intr = wait_fatal_freezable(fc->blocked_waitq,
> + !fuse_block_alloc(fc, for_background), true);
> + restore_sigs(&oldset);
> + if (intr)
> goto out;
> }
> /* Matches smp_wmb() in fuse_set_initialized() */
> @@ -427,9 +446,12 @@ static void request_wait_answer(struct fuse_conn *fc, struct fuse_req *req)
> }
>
> if (!test_bit(FR_FORCE, &req->flags)) {
> + sigset_t oldset;
> /* Only fatal signals may interrupt this */
> - err = wait_event_killable(req->waitq,
> - test_bit(FR_FINISHED, &req->flags));
> + block_sigs(&oldset);
> + err = wait_fatal_freezable(req->waitq,
> + test_bit(FR_FINISHED, &req->flags), false);
> + restore_sigs(&oldset);
> if (!err)
> return;
>
> diff --git a/include/linux/freezer.h b/include/linux/freezer.h
> index dd03e83..2504cd0 100644
> --- a/include/linux/freezer.h
> +++ b/include/linux/freezer.h
> @@ -256,6 +256,22 @@ static inline int freezable_schedule_hrtimeout_range(ktime_t *expires,
> __retval; \
> })
>
> +#define wait_fatal_freezable(wq, condition, exclusive) \
> +({ \
> + int __ret = 0; \
> + do { \
> + if (exclusive) \
> + __ret = wait_event_interruptible_exclusive(wq, \
> + condition); \
> + else \
> + __ret = wait_event_interruptible(wq, \
> + condition); \
> + if (!__ret || fatal_signal_pending(current)) \
> + break; \
> + } while (try_to_freeze()); \
> + __ret; \
> +})
> +
> #else /* !CONFIG_FREEZER */
> static inline bool frozen(struct task_struct *p) { return false; }
> static inline bool freezing(struct task_struct *p) { return false; }
> @@ -296,6 +312,16 @@ static inline void set_freezable(void) {}
> #define wait_event_freezekillable_unsafe(wq, condition) \
> wait_event_killable(wq, condition)
>
> +#define wait_fatal_freezable(wq, condition, exclusive) \
> +({ \
> + int __ret = 0; \
> + if (exclusive) \
> + __ret = wait_event_killable_exclusive(wq, condition); \
> + else \
> + __ret = wait_event_killable(wq, condition); \
> + __ret; \
> +})
> +
> #endif /* !CONFIG_FREEZER */
>
> #endif /* FREEZER_H_INCLUDED */
>
Thanks,
Rafael
^ permalink raw reply [flat|nested] 14+ messages in thread
* 答复: [PATCH] fuse: freezing abort when use wait_event_killable{,_exclusive}().
2016-12-08 6:31 ` 答复: " 崔立飞
@ 2016-12-14 10:09 ` 崔立飞
2016-12-15 22:40 ` Rafael J. Wysocki
2016-12-16 1:34 ` 崔立飞
1 sibling, 1 reply; 14+ messages in thread
From: 崔立飞 @ 2016-12-14 10:09 UTC (permalink / raw)
To: Rafael J. Wysocki
Cc: linux-kernel, miklos, pavel, len.brown, linux-fsdevel, viro,
朴英敏, 刘才,
Jiri Kosina
Rafael,
Any questions about the patch, please let me know.
Thanks!
BR,
Cui Li Fei
________________________________________
发件人: 崔立飞
发送时间: 2016年12月8日 14:31
收件人: Rafael J. Wysocki
抄送: linux-kernel@vger.kernel.org; miklos@szeredi.hu; pavel@ucw.cz; len.brown@intel.com; linux-fsdevel@vger.kernel.org; viro@zeniv.linux.org.uk; 朴英敏; 刘才; Jiri Kosina; 崔立飞
主题: 答复: [PATCH] fuse: freezing abort when use wait_event_killable{,_exclusive}().
Hi Rafael,
The fuse we used is without the commit "fuse: don't mess with blocking signals" committed by Al Viro.
So we find the issue SIGBUS. In the page fault, trying to read page in fuse is interrupted,
which will lead to SIGBUS issue.
All Android platforms, include Android N, have the SIGUBS issue. All the SIGBUS issues are produced
in the freezing process.
In our Android platform, the root-cause of SIGBUS is :
suspend procedure will set the signal pending flag(TIF_SIGPENDING) and then wake up the task
which is TASK_INTERRUPTIBLE status . The request_wait_answer, which calls wait_event_interruptible,
is interrupted and the fuse request is still in pending status, which leads to SIGBUS sent to caller.
This issue can be reproduced by adding delays in funciton handle_read,
which is in the Android sdcard daemon process.
So we merge the commit "fuse: don't mess with blocking signals", which just use wait_event_killable{,_exclusive}().
It fix the SIGBUS issue. But the freezing will fail, because the freezing procedure cannot wake up the task which
is in TASK_KILLABLE(TASK_WAKEKILL | TASK_UNINTERRUPTIBLE) status. And the suspend procedure will abort
until the time is out.
In this patch, we try to fix the issue mentioned above.
> ---
> fs/fuse/dev.c | 30 ++++++++++++++++++++++++++----
> include/linux/freezer.h | 26 ++++++++++++++++++++++++++
> 2 files changed, 52 insertions(+), 4 deletions(-)
>
> diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c
> index 70ea57c..e33a081 100644
> --- a/fs/fuse/dev.c
> +++ b/fs/fuse/dev.c
> @@ -19,6 +19,7 @@
> #include <linux/pipe_fs_i.h>
> #include <linux/swap.h>
> #include <linux/splice.h>
> +#include <linux/freezer.h>
>
> MODULE_ALIAS_MISCDEV(FUSE_MINOR);
> MODULE_ALIAS("devname:fuse");
> @@ -99,6 +100,19 @@ void fuse_request_free(struct fuse_req *req)
> kmem_cache_free(fuse_req_cachep, req);
> }
>
> +static void block_sigs(sigset_t *oldset)
> +{
> + sigset_t mask;
> +
> + siginitsetinv(&mask, sigmask(SIGKILL));
> + sigprocmask(SIG_BLOCK, &mask, oldset);
> +}
> +
> +static void restore_sigs(sigset_t *oldset)
> +{
> + sigprocmask(SIG_SETMASK, oldset, NULL);
> +}
> +
> void __fuse_get_request(struct fuse_req *req)
> {
> atomic_inc(&req->count);
> @@ -134,13 +148,18 @@ static struct fuse_req *__fuse_get_req(struct fuse_conn *fc, unsigned npages,
> bool for_background)
> {
> struct fuse_req *req;
> + sigset_t oldset;
> + int intr;
> int err;
> atomic_inc(&fc->num_waiting);
>
> if (fuse_block_alloc(fc, for_background)) {
> err = -EINTR;
> - if (wait_event_killable_exclusive(fc->blocked_waitq,
> - !fuse_block_alloc(fc, for_background)))
> + block_sigs(&oldset);
> + intr = wait_fatal_freezable(fc->blocked_waitq,
> + !fuse_block_alloc(fc, for_background), true);
> + restore_sigs(&oldset);
> + if (intr)
> goto out;
> }
> /* Matches smp_wmb() in fuse_set_initialized() */
> @@ -427,9 +446,12 @@ static void request_wait_answer(struct fuse_conn *fc, struct fuse_req *req)
> }
>
> if (!test_bit(FR_FORCE, &req->flags)) {
> + sigset_t oldset;
> /* Only fatal signals may interrupt this */
> - err = wait_event_killable(req->waitq,
> - test_bit(FR_FINISHED, &req->flags));
> + block_sigs(&oldset);
> + err = wait_fatal_freezable(req->waitq,
> + test_bit(FR_FINISHED, &req->flags), false);
> + restore_sigs(&oldset);
> if (!err)
> return;
>
> diff --git a/include/linux/freezer.h b/include/linux/freezer.h
> index dd03e83..2504cd0 100644
> --- a/include/linux/freezer.h
> +++ b/include/linux/freezer.h
> @@ -256,6 +256,22 @@ static inline int freezable_schedule_hrtimeout_range(ktime_t *expires,
> __retval; \
> })
>
> +#define wait_fatal_freezable(wq, condition, exclusive) \
> +({ \
> + int __ret = 0; \
> + do { \
> + if (exclusive) \
> + __ret = wait_event_interruptible_exclusive(wq, \ //set the TASK_INTERRUPTIBLE
> + condition); \ //can be waked up by suspend procedure
> + else \
> + __ret = wait_event_interruptible(wq, \
> + condition); \
> + if (!__ret || fatal_signal_pending(current)) \ //check condition or there is fatal signal
> + break; \ //if true, wait finish
> + } while (try_to_freeze()); \ //if freezing is in effect, try to freeze the task
> + __ret; \
> +})
> +
> #else /* !CONFIG_FREEZER */
> static inline bool frozen(struct task_struct *p) { return false; }
> static inline bool freezing(struct task_struct *p) { return false; }
> @@ -296,6 +312,16 @@ static inline void set_freezable(void) {}
> #define wait_event_freezekillable_unsafe(wq, condition) \
> wait_event_killable(wq, condition)
>
> +#define wait_fatal_freezable(wq, condition, exclusive) \
> +({ \
> + int __ret = 0; \
> + if (exclusive) \
> + __ret = wait_event_killable_exclusive(wq, condition); \
> + else \
> + __ret = wait_event_killable(wq, condition); \
> + __ret; \
> +})
> +
> #endif /* !CONFIG_FREEZER */
>
> #endif /* FREEZER_H_INCLUDED */
>
Thanks.
BR,
________________________________________
发件人: Rafael J. Wysocki <rjw@rjwysocki.net>
发送时间: 2016年12月7日 6:15
收件人: 崔立飞
抄送: linux-kernel@vger.kernel.org; miklos@szeredi.hu; pavel@ucw.cz; len.brown@intel.com; linux-fsdevel@vger.kernel.org; viro@zeniv.linux.org.uk; 朴英敏; 刘才; Jiri Kosina
主题: Re: [PATCH] fuse: freezing abort when use wait_event_killable{,_exclusive}().
On Monday, December 05, 2016 11:19:45 AM cuilifei wrote:
> Freezing process can abort when a client is waiting uninterruptibly
> for a response. Add new macro wait_fatal_freezable to try to fix it.
>
> Signed-off-by: cuilifei <cuilifei@xiaomi.com>
I'm not a big fan of this to be honest.
Do we really want to suspend the system (or freeze tasks for other reasons)
if that happens?
> ---
> fs/fuse/dev.c | 30 ++++++++++++++++++++++++++----
> include/linux/freezer.h | 26 ++++++++++++++++++++++++++
> 2 files changed, 52 insertions(+), 4 deletions(-)
>
> diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c
> index 70ea57c..e33a081 100644
> --- a/fs/fuse/dev.c
> +++ b/fs/fuse/dev.c
> @@ -19,6 +19,7 @@
> #include <linux/pipe_fs_i.h>
> #include <linux/swap.h>
> #include <linux/splice.h>
> +#include <linux/freezer.h>
>
> MODULE_ALIAS_MISCDEV(FUSE_MINOR);
> MODULE_ALIAS("devname:fuse");
> @@ -99,6 +100,19 @@ void fuse_request_free(struct fuse_req *req)
> kmem_cache_free(fuse_req_cachep, req);
> }
>
> +static void block_sigs(sigset_t *oldset)
> +{
> + sigset_t mask;
> +
> + siginitsetinv(&mask, sigmask(SIGKILL));
> + sigprocmask(SIG_BLOCK, &mask, oldset);
> +}
> +
> +static void restore_sigs(sigset_t *oldset)
> +{
> + sigprocmask(SIG_SETMASK, oldset, NULL);
> +}
> +
> void __fuse_get_request(struct fuse_req *req)
> {
> atomic_inc(&req->count);
> @@ -134,13 +148,18 @@ static struct fuse_req *__fuse_get_req(struct fuse_conn *fc, unsigned npages,
> bool for_background)
> {
> struct fuse_req *req;
> + sigset_t oldset;
> + int intr;
> int err;
> atomic_inc(&fc->num_waiting);
>
> if (fuse_block_alloc(fc, for_background)) {
> err = -EINTR;
> - if (wait_event_killable_exclusive(fc->blocked_waitq,
> - !fuse_block_alloc(fc, for_background)))
> + block_sigs(&oldset);
> + intr = wait_fatal_freezable(fc->blocked_waitq,
> + !fuse_block_alloc(fc, for_background), true);
> + restore_sigs(&oldset);
> + if (intr)
> goto out;
> }
> /* Matches smp_wmb() in fuse_set_initialized() */
> @@ -427,9 +446,12 @@ static void request_wait_answer(struct fuse_conn *fc, struct fuse_req *req)
> }
>
> if (!test_bit(FR_FORCE, &req->flags)) {
> + sigset_t oldset;
> /* Only fatal signals may interrupt this */
> - err = wait_event_killable(req->waitq,
> - test_bit(FR_FINISHED, &req->flags));
> + block_sigs(&oldset);
> + err = wait_fatal_freezable(req->waitq,
> + test_bit(FR_FINISHED, &req->flags), false);
> + restore_sigs(&oldset);
> if (!err)
> return;
>
> diff --git a/include/linux/freezer.h b/include/linux/freezer.h
> index dd03e83..2504cd0 100644
> --- a/include/linux/freezer.h
> +++ b/include/linux/freezer.h
> @@ -256,6 +256,22 @@ static inline int freezable_schedule_hrtimeout_range(ktime_t *expires,
> __retval; \
> })
>
> +#define wait_fatal_freezable(wq, condition, exclusive) \
> +({ \
> + int __ret = 0; \
> + do { \
> + if (exclusive) \
> + __ret = wait_event_interruptible_exclusive(wq, \
> + condition); \
> + else \
> + __ret = wait_event_interruptible(wq, \
> + condition); \
> + if (!__ret || fatal_signal_pending(current)) \
> + break; \
> + } while (try_to_freeze()); \
> + __ret; \
> +})
> +
> #else /* !CONFIG_FREEZER */
> static inline bool frozen(struct task_struct *p) { return false; }
> static inline bool freezing(struct task_struct *p) { return false; }
> @@ -296,6 +312,16 @@ static inline void set_freezable(void) {}
> #define wait_event_freezekillable_unsafe(wq, condition) \
> wait_event_killable(wq, condition)
>
> +#define wait_fatal_freezable(wq, condition, exclusive) \
> +({ \
> + int __ret = 0; \
> + if (exclusive) \
> + __ret = wait_event_killable_exclusive(wq, condition); \
> + else \
> + __ret = wait_event_killable(wq, condition); \
> + __ret; \
> +})
> +
> #endif /* !CONFIG_FREEZER */
>
> #endif /* FREEZER_H_INCLUDED */
>
Thanks,
Rafael
^ permalink raw reply [flat|nested] 14+ messages in thread
* Re: 答复: [PATCH] fuse: freezing abort when use wait_event_killable{,_exclusive}().
2016-12-14 10:09 ` 崔立飞
@ 2016-12-15 22:40 ` Rafael J. Wysocki
0 siblings, 0 replies; 14+ messages in thread
From: Rafael J. Wysocki @ 2016-12-15 22:40 UTC (permalink / raw)
To: 崔立飞
Cc: linux-kernel, miklos, pavel, len.brown, linux-fsdevel, viro,
朴英敏, 刘才,
Jiri Kosina
On Wednesday, December 14, 2016 10:09:25 AM 崔立飞 wrote:
> Rafael,
>
> Any questions about the patch, please let me know.
To be honest, I don't particularly like it, but I wonder what FUSE maintainers
think about it.
Thanks,
Rafael
^ permalink raw reply [flat|nested] 14+ messages in thread
* 答复: [PATCH] fuse: freezing abort when use wait_event_killable{,_exclusive}().
2016-12-08 6:31 ` 答复: " 崔立飞
2016-12-14 10:09 ` 崔立飞
@ 2016-12-16 1:34 ` 崔立飞
1 sibling, 0 replies; 14+ messages in thread
From: 崔立飞 @ 2016-12-16 1:34 UTC (permalink / raw)
To: miklos
Cc: linux-kernel, pavel, len.brown, linux-fsdevel, viro,
朴英敏, 刘才,
Jiri Kosina, rjw
Hi Miklos,
Please help to review the patch.
Thanks.
________________________________________
发件人: 崔立飞
发送时间: 2016年12月8日 14:31
收件人: Rafael J. Wysocki
抄送: linux-kernel@vger.kernel.org; miklos@szeredi.hu; pavel@ucw.cz; len.brown@intel.com; linux-fsdevel@vger.kernel.org; viro@zeniv.linux.org.uk; 朴英敏; 刘才; Jiri Kosina; 崔立飞
主题: 答复: [PATCH] fuse: freezing abort when use wait_event_killable{,_exclusive}().
Hi Rafael,
The fuse we used is without the commit "fuse: don't mess with blocking signals" committed by Al Viro.
So we find the issue SIGBUS. In the page fault, trying to read page in fuse is interrupted,
which will lead to SIGBUS issue.
All Android platforms, include Android N, have the SIGUBS issue. All the SIGBUS issues are produced
in the freezing process.
In our Android platform, the root-cause of SIGBUS is :
suspend procedure will set the signal pending flag(TIF_SIGPENDING) and then wake up the task
which is TASK_INTERRUPTIBLE status . The request_wait_answer, which calls wait_event_interruptible,
is interrupted and the fuse request is still in pending status, which leads to SIGBUS sent to caller.
This issue can be reproduced by adding delays in funciton handle_read,
which is in the Android sdcard daemon process.
So we merge the commit "fuse: don't mess with blocking signals", which just use wait_event_killable{,_exclusive}().
It fix the SIGBUS issue. But the freezing will fail, because the freezing procedure cannot wake up the task which
is in TASK_KILLABLE(TASK_WAKEKILL | TASK_UNINTERRUPTIBLE) status. And the suspend procedure will abort
until the time is out.
In this patch, we try to fix the issue mentioned above.
> ---
> fs/fuse/dev.c | 30 ++++++++++++++++++++++++++----
> include/linux/freezer.h | 26 ++++++++++++++++++++++++++
> 2 files changed, 52 insertions(+), 4 deletions(-)
>
> diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c
> index 70ea57c..e33a081 100644
> --- a/fs/fuse/dev.c
> +++ b/fs/fuse/dev.c
> @@ -19,6 +19,7 @@
> #include <linux/pipe_fs_i.h>
> #include <linux/swap.h>
> #include <linux/splice.h>
> +#include <linux/freezer.h>
>
> MODULE_ALIAS_MISCDEV(FUSE_MINOR);
> MODULE_ALIAS("devname:fuse");
> @@ -99,6 +100,19 @@ void fuse_request_free(struct fuse_req *req)
> kmem_cache_free(fuse_req_cachep, req);
> }
>
> +static void block_sigs(sigset_t *oldset)
> +{
> + sigset_t mask;
> +
> + siginitsetinv(&mask, sigmask(SIGKILL));
> + sigprocmask(SIG_BLOCK, &mask, oldset);
> +}
> +
> +static void restore_sigs(sigset_t *oldset)
> +{
> + sigprocmask(SIG_SETMASK, oldset, NULL);
> +}
> +
> void __fuse_get_request(struct fuse_req *req)
> {
> atomic_inc(&req->count);
> @@ -134,13 +148,18 @@ static struct fuse_req *__fuse_get_req(struct fuse_conn *fc, unsigned npages,
> bool for_background)
> {
> struct fuse_req *req;
> + sigset_t oldset;
> + int intr;
> int err;
> atomic_inc(&fc->num_waiting);
>
> if (fuse_block_alloc(fc, for_background)) {
> err = -EINTR;
> - if (wait_event_killable_exclusive(fc->blocked_waitq,
> - !fuse_block_alloc(fc, for_background)))
> + block_sigs(&oldset);
> + intr = wait_fatal_freezable(fc->blocked_waitq,
> + !fuse_block_alloc(fc, for_background), true);
> + restore_sigs(&oldset);
> + if (intr)
> goto out;
> }
> /* Matches smp_wmb() in fuse_set_initialized() */
> @@ -427,9 +446,12 @@ static void request_wait_answer(struct fuse_conn *fc, struct fuse_req *req)
> }
>
> if (!test_bit(FR_FORCE, &req->flags)) {
> + sigset_t oldset;
> /* Only fatal signals may interrupt this */
> - err = wait_event_killable(req->waitq,
> - test_bit(FR_FINISHED, &req->flags));
> + block_sigs(&oldset);
> + err = wait_fatal_freezable(req->waitq,
> + test_bit(FR_FINISHED, &req->flags), false);
> + restore_sigs(&oldset);
> if (!err)
> return;
>
> diff --git a/include/linux/freezer.h b/include/linux/freezer.h
> index dd03e83..2504cd0 100644
> --- a/include/linux/freezer.h
> +++ b/include/linux/freezer.h
> @@ -256,6 +256,22 @@ static inline int freezable_schedule_hrtimeout_range(ktime_t *expires,
> __retval; \
> })
>
> +#define wait_fatal_freezable(wq, condition, exclusive) \
> +({ \
> + int __ret = 0; \
> + do { \
> + if (exclusive) \
> + __ret = wait_event_interruptible_exclusive(wq, \ //set the TASK_INTERRUPTIBLE
> + condition); \ //can be waked up by suspend procedure
> + else \
> + __ret = wait_event_interruptible(wq, \
> + condition); \
> + if (!__ret || fatal_signal_pending(current)) \ //check condition or there is fatal signal
> + break; \ //if true, wait finish
> + } while (try_to_freeze()); \ //if freezing is in effect, try to freeze the task
> + __ret; \
> +})
> +
> #else /* !CONFIG_FREEZER */
> static inline bool frozen(struct task_struct *p) { return false; }
> static inline bool freezing(struct task_struct *p) { return false; }
> @@ -296,6 +312,16 @@ static inline void set_freezable(void) {}
> #define wait_event_freezekillable_unsafe(wq, condition) \
> wait_event_killable(wq, condition)
>
> +#define wait_fatal_freezable(wq, condition, exclusive) \
> +({ \
> + int __ret = 0; \
> + if (exclusive) \
> + __ret = wait_event_killable_exclusive(wq, condition); \
> + else \
> + __ret = wait_event_killable(wq, condition); \
> + __ret; \
> +})
> +
> #endif /* !CONFIG_FREEZER */
>
> #endif /* FREEZER_H_INCLUDED */
>
Thanks.
BR,
________________________________________
发件人: Rafael J. Wysocki <rjw@rjwysocki.net>
发送时间: 2016年12月7日 6:15
收件人: 崔立飞
抄送: linux-kernel@vger.kernel.org; miklos@szeredi.hu; pavel@ucw.cz; len.brown@intel.com; linux-fsdevel@vger.kernel.org; viro@zeniv.linux.org.uk; 朴英敏; 刘才; Jiri Kosina
主题: Re: [PATCH] fuse: freezing abort when use wait_event_killable{,_exclusive}().
On Monday, December 05, 2016 11:19:45 AM cuilifei wrote:
> Freezing process can abort when a client is waiting uninterruptibly
> for a response. Add new macro wait_fatal_freezable to try to fix it.
>
> Signed-off-by: cuilifei <cuilifei@xiaomi.com>
I'm not a big fan of this to be honest.
Do we really want to suspend the system (or freeze tasks for other reasons)
if that happens?
> ---
> fs/fuse/dev.c | 30 ++++++++++++++++++++++++++----
> include/linux/freezer.h | 26 ++++++++++++++++++++++++++
> 2 files changed, 52 insertions(+), 4 deletions(-)
>
> diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c
> index 70ea57c..e33a081 100644
> --- a/fs/fuse/dev.c
> +++ b/fs/fuse/dev.c
> @@ -19,6 +19,7 @@
> #include <linux/pipe_fs_i.h>
> #include <linux/swap.h>
> #include <linux/splice.h>
> +#include <linux/freezer.h>
>
> MODULE_ALIAS_MISCDEV(FUSE_MINOR);
> MODULE_ALIAS("devname:fuse");
> @@ -99,6 +100,19 @@ void fuse_request_free(struct fuse_req *req)
> kmem_cache_free(fuse_req_cachep, req);
> }
>
> +static void block_sigs(sigset_t *oldset)
> +{
> + sigset_t mask;
> +
> + siginitsetinv(&mask, sigmask(SIGKILL));
> + sigprocmask(SIG_BLOCK, &mask, oldset);
> +}
> +
> +static void restore_sigs(sigset_t *oldset)
> +{
> + sigprocmask(SIG_SETMASK, oldset, NULL);
> +}
> +
> void __fuse_get_request(struct fuse_req *req)
> {
> atomic_inc(&req->count);
> @@ -134,13 +148,18 @@ static struct fuse_req *__fuse_get_req(struct fuse_conn *fc, unsigned npages,
> bool for_background)
> {
> struct fuse_req *req;
> + sigset_t oldset;
> + int intr;
> int err;
> atomic_inc(&fc->num_waiting);
>
> if (fuse_block_alloc(fc, for_background)) {
> err = -EINTR;
> - if (wait_event_killable_exclusive(fc->blocked_waitq,
> - !fuse_block_alloc(fc, for_background)))
> + block_sigs(&oldset);
> + intr = wait_fatal_freezable(fc->blocked_waitq,
> + !fuse_block_alloc(fc, for_background), true);
> + restore_sigs(&oldset);
> + if (intr)
> goto out;
> }
> /* Matches smp_wmb() in fuse_set_initialized() */
> @@ -427,9 +446,12 @@ static void request_wait_answer(struct fuse_conn *fc, struct fuse_req *req)
> }
>
> if (!test_bit(FR_FORCE, &req->flags)) {
> + sigset_t oldset;
> /* Only fatal signals may interrupt this */
> - err = wait_event_killable(req->waitq,
> - test_bit(FR_FINISHED, &req->flags));
> + block_sigs(&oldset);
> + err = wait_fatal_freezable(req->waitq,
> + test_bit(FR_FINISHED, &req->flags), false);
> + restore_sigs(&oldset);
> if (!err)
> return;
>
> diff --git a/include/linux/freezer.h b/include/linux/freezer.h
> index dd03e83..2504cd0 100644
> --- a/include/linux/freezer.h
> +++ b/include/linux/freezer.h
> @@ -256,6 +256,22 @@ static inline int freezable_schedule_hrtimeout_range(ktime_t *expires,
> __retval; \
> })
>
> +#define wait_fatal_freezable(wq, condition, exclusive) \
> +({ \
> + int __ret = 0; \
> + do { \
> + if (exclusive) \
> + __ret = wait_event_interruptible_exclusive(wq, \
> + condition); \
> + else \
> + __ret = wait_event_interruptible(wq, \
> + condition); \
> + if (!__ret || fatal_signal_pending(current)) \
> + break; \
> + } while (try_to_freeze()); \
> + __ret; \
> +})
> +
> #else /* !CONFIG_FREEZER */
> static inline bool frozen(struct task_struct *p) { return false; }
> static inline bool freezing(struct task_struct *p) { return false; }
> @@ -296,6 +312,16 @@ static inline void set_freezable(void) {}
> #define wait_event_freezekillable_unsafe(wq, condition) \
> wait_event_killable(wq, condition)
>
> +#define wait_fatal_freezable(wq, condition, exclusive) \
> +({ \
> + int __ret = 0; \
> + if (exclusive) \
> + __ret = wait_event_killable_exclusive(wq, condition); \
> + else \
> + __ret = wait_event_killable(wq, condition); \
> + __ret; \
> +})
> +
> #endif /* !CONFIG_FREEZER */
>
> #endif /* FREEZER_H_INCLUDED */
>
Thanks,
Rafael
^ permalink raw reply [flat|nested] 14+ messages in thread
* Re: [PATCH] fuse: freezing abort when use wait_event_killable{,_exclusive}().
2016-12-02 7:26 cuilifei
@ 2016-12-03 8:54 ` kbuild test robot
0 siblings, 0 replies; 14+ messages in thread
From: kbuild test robot @ 2016-12-03 8:54 UTC (permalink / raw)
To: cuilifei; +Cc: kbuild-all, linux-kernel, miklos, cuilifei
[-- Attachment #1: Type: text/plain, Size: 1573 bytes --]
Hi cuilifei,
[auto build test ERROR on fuse/for-next]
[also build test ERROR on v4.9-rc7 next-20161202]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]
url: https://github.com/0day-ci/linux/commits/cuilifei/fuse-freezing-abort-when-use-wait_event_killable-_exclusive/20161203-120253
base: https://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse.git for-next
config: x86_64-rhel-7.2 (attached as .config)
compiler: gcc-6 (Debian 6.2.0-3) 6.2.0 20160901
reproduce:
# save the attached .config to linux build tree
make ARCH=x86_64
All errors (new ones prefixed by >>):
fs/fuse/dev.c: In function '__fuse_get_req':
>> fs/fuse/dev.c:38:11: error: implicit declaration of function 'try_to_freeze' [-Werror=implicit-function-declaration]
} while (try_to_freeze()); \
^
fs/fuse/dev.c:174:10: note: in expansion of macro 'wait_fatal_freezable'
intr = wait_fatal_freezable(fc->blocked_waitq,
^~~~~~~~~~~~~~~~~~~~
cc1: some warnings being treated as errors
vim +/try_to_freeze +38 fs/fuse/dev.c
32 condition); \
33 else \
34 __ret = wait_event_interruptible(wq, \
35 condition); \
36 if (!__ret || fatal_signal_pending(current)) \
37 break; \
> 38 } while (try_to_freeze()); \
39 __ret; \
40 })
41
---
0-DAY kernel test infrastructure Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all Intel Corporation
[-- Attachment #2: .config.gz --]
[-- Type: application/gzip, Size: 37906 bytes --]
^ permalink raw reply [flat|nested] 14+ messages in thread
* Re: [PATCH] fuse: freezing abort when use wait_event_killable{,_exclusive}().
2016-12-01 5:43 cuilifei
2016-12-02 16:16 ` kbuild test robot
@ 2016-12-02 18:42 ` kbuild test robot
1 sibling, 0 replies; 14+ messages in thread
From: kbuild test robot @ 2016-12-02 18:42 UTC (permalink / raw)
To: cuilifei; +Cc: kbuild-all, linux-kernel, miklos, cuilifei
[-- Attachment #1: Type: text/plain, Size: 1956 bytes --]
Hi cuilifei,
[auto build test ERROR on fuse/for-next]
[also build test ERROR on v4.9-rc7 next-20161202]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]
url: https://github.com/0day-ci/linux/commits/cuilifei/fuse-freezing-abort-when-use-wait_event_killable-_exclusive/20161202-234345
base: https://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse.git for-next
config: x86_64-kexec (attached as .config)
compiler: gcc-6 (Debian 6.2.0-3) 6.2.0 20160901
reproduce:
# save the attached .config to linux build tree
make ARCH=x86_64
All errors (new ones prefixed by >>):
fs/fuse/dev.c: In function '__fuse_get_req':
>> fs/fuse/dev.c:38:8: error: implicit declaration of function 'freezing' [-Werror=implicit-function-declaration]
if (!freezing(current)) \
^
fs/fuse/dev.c:176:10: note: in expansion of macro 'wait_fatal_freezable'
intr = wait_fatal_freezable(fc->blocked_waitq,
^~~~~~~~~~~~~~~~~~~~
>> fs/fuse/dev.c:40:11: error: implicit declaration of function 'try_to_freeze' [-Werror=implicit-function-declaration]
} while (try_to_freeze()); \
^
fs/fuse/dev.c:176:10: note: in expansion of macro 'wait_fatal_freezable'
intr = wait_fatal_freezable(fc->blocked_waitq,
^~~~~~~~~~~~~~~~~~~~
cc1: some warnings being treated as errors
vim +/freezing +38 fs/fuse/dev.c
32 condition); \
33 else \
34 __ret = wait_event_interruptible(wq, \
35 condition); \
36 if (!__ret || fatal_signal_pending(current)) \
37 break; \
> 38 if (!freezing(current)) \
39 continue; \
> 40 } while (try_to_freeze()); \
41 __ret; \
42 })
43
---
0-DAY kernel test infrastructure Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all Intel Corporation
[-- Attachment #2: .config.gz --]
[-- Type: application/gzip, Size: 24266 bytes --]
^ permalink raw reply [flat|nested] 14+ messages in thread
* Re: [PATCH] fuse: freezing abort when use wait_event_killable{,_exclusive}().
2016-12-01 5:43 cuilifei
@ 2016-12-02 16:16 ` kbuild test robot
2016-12-02 18:42 ` kbuild test robot
1 sibling, 0 replies; 14+ messages in thread
From: kbuild test robot @ 2016-12-02 16:16 UTC (permalink / raw)
To: cuilifei; +Cc: kbuild-all, linux-kernel, miklos, cuilifei
[-- Attachment #1: Type: text/plain, Size: 3564 bytes --]
Hi cuilifei,
[auto build test WARNING on fuse/for-next]
[also build test WARNING on v4.9-rc7 next-20161202]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]
url: https://github.com/0day-ci/linux/commits/cuilifei/fuse-freezing-abort-when-use-wait_event_killable-_exclusive/20161202-234345
base: https://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse.git for-next
config: x86_64-randconfig-x013-201648 (attached as .config)
compiler: gcc-6 (Debian 6.2.0-3) 6.2.0 20160901
reproduce:
# save the attached .config to linux build tree
make ARCH=x86_64
All warnings (new ones prefixed by >>):
In file included from include/uapi/linux/stddef.h:1:0,
from include/linux/stddef.h:4,
from include/uapi/linux/posix_types.h:4,
from include/uapi/linux/types.h:13,
from include/linux/types.h:5,
from include/uapi/linux/fuse.h:121,
from fs/fuse/fuse_i.h:12,
from fs/fuse/dev.c:9:
fs/fuse/dev.c: In function '__fuse_get_req':
fs/fuse/dev.c:38:8: error: implicit declaration of function 'freezing' [-Werror=implicit-function-declaration]
if (!freezing(current)) \
^
include/linux/compiler.h:149:30: note: in definition of macro '__trace_if'
if (__builtin_constant_p(!!(cond)) ? !!(cond) : \
^~~~
>> fs/fuse/dev.c:38:3: note: in expansion of macro 'if'
if (!freezing(current)) \
^~
fs/fuse/dev.c:176:10: note: in expansion of macro 'wait_fatal_freezable'
intr = wait_fatal_freezable(fc->blocked_waitq,
^~~~~~~~~~~~~~~~~~~~
fs/fuse/dev.c:40:11: error: implicit declaration of function 'try_to_freeze' [-Werror=implicit-function-declaration]
} while (try_to_freeze()); \
^
fs/fuse/dev.c:176:10: note: in expansion of macro 'wait_fatal_freezable'
intr = wait_fatal_freezable(fc->blocked_waitq,
^~~~~~~~~~~~~~~~~~~~
cc1: some warnings being treated as errors
vim +/if +38 fs/fuse/dev.c
3 Copyright (C) 2001-2008 Miklos Szeredi <miklos@szeredi.hu>
4
5 This program can be distributed under the terms of the GNU GPL.
6 See the file COPYING.
7 */
8
> 9 #include "fuse_i.h"
10
11 #include <linux/init.h>
12 #include <linux/module.h>
13 #include <linux/poll.h>
14 #include <linux/uio.h>
15 #include <linux/miscdevice.h>
16 #include <linux/pagemap.h>
17 #include <linux/file.h>
18 #include <linux/slab.h>
19 #include <linux/pipe_fs_i.h>
20 #include <linux/swap.h>
21 #include <linux/splice.h>
22
23 MODULE_ALIAS_MISCDEV(FUSE_MINOR);
24 MODULE_ALIAS("devname:fuse");
25
26 #define wait_fatal_freezable(wq, condition, exclusive) \
27 ({ \
28 int __ret = 0; \
29 do { \
30 if (exclusive) \
31 __ret = wait_event_interruptible_exclusive(wq, \
32 condition); \
33 else \
34 __ret = wait_event_interruptible(wq, \
35 condition); \
36 if (!__ret || fatal_signal_pending(current)) \
37 break; \
> 38 if (!freezing(current)) \
39 continue; \
40 } while (try_to_freeze()); \
41 __ret; \
---
0-DAY kernel test infrastructure Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all Intel Corporation
[-- Attachment #2: .config.gz --]
[-- Type: application/gzip, Size: 18547 bytes --]
^ permalink raw reply [flat|nested] 14+ messages in thread
* Re: [PATCH] fuse: freezing abort when use wait_event_killable{,_exclusive}().
2016-12-01 5:37 cuilifei
2016-12-02 14:42 ` kbuild test robot
@ 2016-12-02 14:51 ` kbuild test robot
1 sibling, 0 replies; 14+ messages in thread
From: kbuild test robot @ 2016-12-02 14:51 UTC (permalink / raw)
To: cuilifei; +Cc: kbuild-all, linux-kernel, miklos, cuilifei
[-- Attachment #1: Type: text/plain, Size: 7189 bytes --]
Hi cuilifei,
[auto build test WARNING on fuse/for-next]
[also build test WARNING on v4.9-rc7 next-20161202]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]
url: https://github.com/0day-ci/linux/commits/cuilifei/fuse-freezing-abort-when-use-wait_event_killable-_exclusive/20161202-221508
base: https://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse.git for-next
config: m68k-sun3_defconfig (attached as .config)
compiler: m68k-linux-gcc (GCC) 4.9.0
reproduce:
wget https://git.kernel.org/cgit/linux/kernel/git/wfg/lkp-tests.git/plain/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# save the attached .config to linux build tree
make.cross ARCH=m68k
All warnings (new ones prefixed by >>):
fs/fuse/dev.c: In function '__fuse_get_req':
fs/fuse/dev.c:31:4: error: 'ret' undeclared (first use in this function)
ret = wait_event_interruptible_exclusive(wq, \
^
>> fs/fuse/dev.c:175:10: note: in expansion of macro 'wait_fatal_freezable'
intr = wait_fatal_freezable(fc->blocked_waitq,
^
fs/fuse/dev.c:31:4: note: each undeclared identifier is reported only once for each function it appears in
ret = wait_event_interruptible_exclusive(wq, \
^
>> fs/fuse/dev.c:175:10: note: in expansion of macro 'wait_fatal_freezable'
intr = wait_fatal_freezable(fc->blocked_waitq,
^
fs/fuse/dev.c:175:3: error: implicit declaration of function 'freezing' [-Werror=implicit-function-declaration]
intr = wait_fatal_freezable(fc->blocked_waitq,
^
fs/fuse/dev.c:175:3: error: implicit declaration of function 'try_to_freeze' [-Werror=implicit-function-declaration]
fs/fuse/dev.c: In function 'request_wait_answer':
fs/fuse/dev.c:31:4: error: 'ret' undeclared (first use in this function)
ret = wait_event_interruptible_exclusive(wq, \
^
fs/fuse/dev.c:468:9: note: in expansion of macro 'wait_fatal_freezable'
err = wait_fatal_freezable(req->waitq,
^
cc1: some warnings being treated as errors
vim +/wait_fatal_freezable +175 fs/fuse/dev.c
25
26 #define wait_fatal_freezable(wq, condition, exclusive) \
27 ({ \
28 int __ret = 0; \
29 do { \
30 if (exclusive) \
> 31 ret = wait_event_interruptible_exclusive(wq, \
32 condition); \
33 else \
34 ret = wait_event_interruptible(wq, condition); \
35 if (!__ret || fatal_signal_pending(current)) \
36 break; \
37 if (!freezing(current)) \
38 continue; \
39 } while (try_to_freeze()); \
40 __ret; \
41 })
42
43 static struct kmem_cache *fuse_req_cachep;
44
45 static struct fuse_dev *fuse_get_dev(struct file *file)
46 {
47 /*
48 * Lockless access is OK, because file->private data is set
49 * once during mount and is valid until the file is released.
50 */
51 return ACCESS_ONCE(file->private_data);
52 }
53
54 static void fuse_request_init(struct fuse_req *req, struct page **pages,
55 struct fuse_page_desc *page_descs,
56 unsigned npages)
57 {
58 memset(req, 0, sizeof(*req));
59 memset(pages, 0, sizeof(*pages) * npages);
60 memset(page_descs, 0, sizeof(*page_descs) * npages);
61 INIT_LIST_HEAD(&req->list);
62 INIT_LIST_HEAD(&req->intr_entry);
63 init_waitqueue_head(&req->waitq);
64 atomic_set(&req->count, 1);
65 req->pages = pages;
66 req->page_descs = page_descs;
67 req->max_pages = npages;
68 __set_bit(FR_PENDING, &req->flags);
69 }
70
71 static struct fuse_req *__fuse_request_alloc(unsigned npages, gfp_t flags)
72 {
73 struct fuse_req *req = kmem_cache_alloc(fuse_req_cachep, flags);
74 if (req) {
75 struct page **pages;
76 struct fuse_page_desc *page_descs;
77
78 if (npages <= FUSE_REQ_INLINE_PAGES) {
79 pages = req->inline_pages;
80 page_descs = req->inline_page_descs;
81 } else {
82 pages = kmalloc(sizeof(struct page *) * npages, flags);
83 page_descs = kmalloc(sizeof(struct fuse_page_desc) *
84 npages, flags);
85 }
86
87 if (!pages || !page_descs) {
88 kfree(pages);
89 kfree(page_descs);
90 kmem_cache_free(fuse_req_cachep, req);
91 return NULL;
92 }
93
94 fuse_request_init(req, pages, page_descs, npages);
95 }
96 return req;
97 }
98
99 struct fuse_req *fuse_request_alloc(unsigned npages)
100 {
101 return __fuse_request_alloc(npages, GFP_KERNEL);
102 }
103 EXPORT_SYMBOL_GPL(fuse_request_alloc);
104
105 struct fuse_req *fuse_request_alloc_nofs(unsigned npages)
106 {
107 return __fuse_request_alloc(npages, GFP_NOFS);
108 }
109
110 void fuse_request_free(struct fuse_req *req)
111 {
112 if (req->pages != req->inline_pages) {
113 kfree(req->pages);
114 kfree(req->page_descs);
115 }
116 kmem_cache_free(fuse_req_cachep, req);
117 }
118
119 static void block_sigs(sigset_t *oldset)
120 {
121 sigset_t mask;
122
123 siginitsetinv(&mask, sigmask(SIGKILL));
124 sigprocmask(SIG_BLOCK, &mask, oldset);
125 }
126
127 static void restore_sigs(sigset_t *oldset)
128 {
129 sigprocmask(SIG_SETMASK, oldset, NULL);
130 }
131
132 void __fuse_get_request(struct fuse_req *req)
133 {
134 atomic_inc(&req->count);
135 }
136
137 /* Must be called with > 1 refcount */
138 static void __fuse_put_request(struct fuse_req *req)
139 {
140 BUG_ON(atomic_read(&req->count) < 2);
141 atomic_dec(&req->count);
142 }
143
144 static void fuse_req_init_context(struct fuse_req *req)
145 {
146 req->in.h.uid = from_kuid_munged(&init_user_ns, current_fsuid());
147 req->in.h.gid = from_kgid_munged(&init_user_ns, current_fsgid());
148 req->in.h.pid = current->pid;
149 }
150
151 void fuse_set_initialized(struct fuse_conn *fc)
152 {
153 /* Make sure stores before this are seen on another CPU */
154 smp_wmb();
155 fc->initialized = 1;
156 }
157
158 static bool fuse_block_alloc(struct fuse_conn *fc, bool for_background)
159 {
160 return !fc->initialized || (for_background && fc->blocked);
161 }
162
163 static struct fuse_req *__fuse_get_req(struct fuse_conn *fc, unsigned npages,
164 bool for_background)
165 {
166 struct fuse_req *req;
167 sigset_t oldset;
168 int intr;
169 int err;
170 atomic_inc(&fc->num_waiting);
171
172 if (fuse_block_alloc(fc, for_background)) {
173 err = -EINTR;
174 block_sigs(&oldset);
> 175 intr = wait_fatal_freezable(fc->blocked_waitq,
176 !fuse_block_alloc(fc, for_background), true);
177 restore_sigs(&oldset);
178 if (intr)
---
0-DAY kernel test infrastructure Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all Intel Corporation
[-- Attachment #2: .config.gz --]
[-- Type: application/gzip, Size: 11509 bytes --]
^ permalink raw reply [flat|nested] 14+ messages in thread
* Re: [PATCH] fuse: freezing abort when use wait_event_killable{,_exclusive}().
2016-12-01 5:37 cuilifei
@ 2016-12-02 14:42 ` kbuild test robot
2016-12-02 14:51 ` kbuild test robot
1 sibling, 0 replies; 14+ messages in thread
From: kbuild test robot @ 2016-12-02 14:42 UTC (permalink / raw)
To: cuilifei; +Cc: kbuild-all, linux-kernel, miklos, cuilifei
[-- Attachment #1: Type: text/plain, Size: 7017 bytes --]
Hi cuilifei,
[auto build test ERROR on fuse/for-next]
[also build test ERROR on v4.9-rc7 next-20161202]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]
url: https://github.com/0day-ci/linux/commits/cuilifei/fuse-freezing-abort-when-use-wait_event_killable-_exclusive/20161202-221508
base: https://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse.git for-next
config: i386-randconfig-i0-201648 (attached as .config)
compiler: gcc-4.8 (Debian 4.8.4-1) 4.8.4
reproduce:
# save the attached .config to linux build tree
make ARCH=i386
All errors (new ones prefixed by >>):
fs/fuse/dev.c: In function '__fuse_get_req':
>> fs/fuse/dev.c:31:4: error: 'ret' undeclared (first use in this function)
ret = wait_event_interruptible_exclusive(wq, \
^
fs/fuse/dev.c:175:10: note: in expansion of macro 'wait_fatal_freezable'
intr = wait_fatal_freezable(fc->blocked_waitq,
^
fs/fuse/dev.c:31:4: note: each undeclared identifier is reported only once for each function it appears in
ret = wait_event_interruptible_exclusive(wq, \
^
fs/fuse/dev.c:175:10: note: in expansion of macro 'wait_fatal_freezable'
intr = wait_fatal_freezable(fc->blocked_waitq,
^
>> fs/fuse/dev.c:175:3: error: implicit declaration of function 'freezing' [-Werror=implicit-function-declaration]
intr = wait_fatal_freezable(fc->blocked_waitq,
^
>> fs/fuse/dev.c:175:3: error: implicit declaration of function 'try_to_freeze' [-Werror=implicit-function-declaration]
fs/fuse/dev.c: In function 'request_wait_answer':
>> fs/fuse/dev.c:31:4: error: 'ret' undeclared (first use in this function)
ret = wait_event_interruptible_exclusive(wq, \
^
fs/fuse/dev.c:468:9: note: in expansion of macro 'wait_fatal_freezable'
err = wait_fatal_freezable(req->waitq,
^
cc1: some warnings being treated as errors
vim +/ret +31 fs/fuse/dev.c
25
26 #define wait_fatal_freezable(wq, condition, exclusive) \
27 ({ \
28 int __ret = 0; \
29 do { \
30 if (exclusive) \
> 31 ret = wait_event_interruptible_exclusive(wq, \
32 condition); \
33 else \
34 ret = wait_event_interruptible(wq, condition); \
35 if (!__ret || fatal_signal_pending(current)) \
36 break; \
37 if (!freezing(current)) \
38 continue; \
39 } while (try_to_freeze()); \
40 __ret; \
41 })
42
43 static struct kmem_cache *fuse_req_cachep;
44
45 static struct fuse_dev *fuse_get_dev(struct file *file)
46 {
47 /*
48 * Lockless access is OK, because file->private data is set
49 * once during mount and is valid until the file is released.
50 */
51 return ACCESS_ONCE(file->private_data);
52 }
53
54 static void fuse_request_init(struct fuse_req *req, struct page **pages,
55 struct fuse_page_desc *page_descs,
56 unsigned npages)
57 {
58 memset(req, 0, sizeof(*req));
59 memset(pages, 0, sizeof(*pages) * npages);
60 memset(page_descs, 0, sizeof(*page_descs) * npages);
61 INIT_LIST_HEAD(&req->list);
62 INIT_LIST_HEAD(&req->intr_entry);
63 init_waitqueue_head(&req->waitq);
64 atomic_set(&req->count, 1);
65 req->pages = pages;
66 req->page_descs = page_descs;
67 req->max_pages = npages;
68 __set_bit(FR_PENDING, &req->flags);
69 }
70
71 static struct fuse_req *__fuse_request_alloc(unsigned npages, gfp_t flags)
72 {
73 struct fuse_req *req = kmem_cache_alloc(fuse_req_cachep, flags);
74 if (req) {
75 struct page **pages;
76 struct fuse_page_desc *page_descs;
77
78 if (npages <= FUSE_REQ_INLINE_PAGES) {
79 pages = req->inline_pages;
80 page_descs = req->inline_page_descs;
81 } else {
82 pages = kmalloc(sizeof(struct page *) * npages, flags);
83 page_descs = kmalloc(sizeof(struct fuse_page_desc) *
84 npages, flags);
85 }
86
87 if (!pages || !page_descs) {
88 kfree(pages);
89 kfree(page_descs);
90 kmem_cache_free(fuse_req_cachep, req);
91 return NULL;
92 }
93
94 fuse_request_init(req, pages, page_descs, npages);
95 }
96 return req;
97 }
98
99 struct fuse_req *fuse_request_alloc(unsigned npages)
100 {
101 return __fuse_request_alloc(npages, GFP_KERNEL);
102 }
103 EXPORT_SYMBOL_GPL(fuse_request_alloc);
104
105 struct fuse_req *fuse_request_alloc_nofs(unsigned npages)
106 {
107 return __fuse_request_alloc(npages, GFP_NOFS);
108 }
109
110 void fuse_request_free(struct fuse_req *req)
111 {
112 if (req->pages != req->inline_pages) {
113 kfree(req->pages);
114 kfree(req->page_descs);
115 }
116 kmem_cache_free(fuse_req_cachep, req);
117 }
118
119 static void block_sigs(sigset_t *oldset)
120 {
121 sigset_t mask;
122
123 siginitsetinv(&mask, sigmask(SIGKILL));
124 sigprocmask(SIG_BLOCK, &mask, oldset);
125 }
126
127 static void restore_sigs(sigset_t *oldset)
128 {
129 sigprocmask(SIG_SETMASK, oldset, NULL);
130 }
131
132 void __fuse_get_request(struct fuse_req *req)
133 {
134 atomic_inc(&req->count);
135 }
136
137 /* Must be called with > 1 refcount */
138 static void __fuse_put_request(struct fuse_req *req)
139 {
140 BUG_ON(atomic_read(&req->count) < 2);
141 atomic_dec(&req->count);
142 }
143
144 static void fuse_req_init_context(struct fuse_req *req)
145 {
146 req->in.h.uid = from_kuid_munged(&init_user_ns, current_fsuid());
147 req->in.h.gid = from_kgid_munged(&init_user_ns, current_fsgid());
148 req->in.h.pid = current->pid;
149 }
150
151 void fuse_set_initialized(struct fuse_conn *fc)
152 {
153 /* Make sure stores before this are seen on another CPU */
154 smp_wmb();
155 fc->initialized = 1;
156 }
157
158 static bool fuse_block_alloc(struct fuse_conn *fc, bool for_background)
159 {
160 return !fc->initialized || (for_background && fc->blocked);
161 }
162
163 static struct fuse_req *__fuse_get_req(struct fuse_conn *fc, unsigned npages,
164 bool for_background)
165 {
166 struct fuse_req *req;
167 sigset_t oldset;
168 int intr;
169 int err;
170 atomic_inc(&fc->num_waiting);
171
172 if (fuse_block_alloc(fc, for_background)) {
173 err = -EINTR;
174 block_sigs(&oldset);
> 175 intr = wait_fatal_freezable(fc->blocked_waitq,
176 !fuse_block_alloc(fc, for_background), true);
177 restore_sigs(&oldset);
178 if (intr)
---
0-DAY kernel test infrastructure Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all Intel Corporation
[-- Attachment #2: .config.gz --]
[-- Type: application/gzip, Size: 23011 bytes --]
^ permalink raw reply [flat|nested] 14+ messages in thread
* [PATCH] fuse: freezing abort when use wait_event_killable{,_exclusive}().
@ 2016-12-02 7:26 cuilifei
2016-12-03 8:54 ` kbuild test robot
0 siblings, 1 reply; 14+ messages in thread
From: cuilifei @ 2016-12-02 7:26 UTC (permalink / raw)
To: linux-kernel; +Cc: miklos, cuilifei
Freezing process can abort when a client is waiting uninterruptibly
for a response. Add new macro wait_fatal_freezable to try to fix it.
Signed-off-by: cuilifei <cuilifei@xiaomi.com>
---
fs/fuse/dev.c | 45 +++++++++++++++++++++++++++++++++++++++++----
1 file changed, 41 insertions(+), 4 deletions(-)
diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c
index 70ea57c..3447ecc 100644
--- a/fs/fuse/dev.c
+++ b/fs/fuse/dev.c
@@ -23,6 +23,22 @@
MODULE_ALIAS_MISCDEV(FUSE_MINOR);
MODULE_ALIAS("devname:fuse");
+#define wait_fatal_freezable(wq, condition, exclusive) \
+({ \
+ int __ret = 0; \
+ do { \
+ if (exclusive) \
+ __ret = wait_event_interruptible_exclusive(wq, \
+ condition); \
+ else \
+ __ret = wait_event_interruptible(wq, \
+ condition); \
+ if (!__ret || fatal_signal_pending(current)) \
+ break; \
+ } while (try_to_freeze()); \
+ __ret; \
+})
+
static struct kmem_cache *fuse_req_cachep;
static struct fuse_dev *fuse_get_dev(struct file *file)
@@ -99,6 +115,19 @@ void fuse_request_free(struct fuse_req *req)
kmem_cache_free(fuse_req_cachep, req);
}
+static void block_sigs(sigset_t *oldset)
+{
+ sigset_t mask;
+
+ siginitsetinv(&mask, sigmask(SIGKILL));
+ sigprocmask(SIG_BLOCK, &mask, oldset);
+}
+
+static void restore_sigs(sigset_t *oldset)
+{
+ sigprocmask(SIG_SETMASK, oldset, NULL);
+}
+
void __fuse_get_request(struct fuse_req *req)
{
atomic_inc(&req->count);
@@ -134,13 +163,18 @@ static struct fuse_req *__fuse_get_req(struct fuse_conn *fc, unsigned npages,
bool for_background)
{
struct fuse_req *req;
+ sigset_t oldset;
+ int intr;
int err;
atomic_inc(&fc->num_waiting);
if (fuse_block_alloc(fc, for_background)) {
err = -EINTR;
- if (wait_event_killable_exclusive(fc->blocked_waitq,
- !fuse_block_alloc(fc, for_background)))
+ block_sigs(&oldset);
+ intr = wait_fatal_freezable(fc->blocked_waitq,
+ !fuse_block_alloc(fc, for_background), true);
+ restore_sigs(&oldset);
+ if (intr)
goto out;
}
/* Matches smp_wmb() in fuse_set_initialized() */
@@ -427,9 +461,12 @@ static void request_wait_answer(struct fuse_conn *fc, struct fuse_req *req)
}
if (!test_bit(FR_FORCE, &req->flags)) {
+ sigset_t oldset;
/* Only fatal signals may interrupt this */
- err = wait_event_killable(req->waitq,
- test_bit(FR_FINISHED, &req->flags));
+ block_sigs(&oldset);
+ err = wait_fatal_freezable(req->waitq,
+ test_bit(FR_FINISHED, &req->flags), false);
+ restore_sigs(&oldset);
if (!err)
return;
--
1.9.1
^ permalink raw reply related [flat|nested] 14+ messages in thread
* [PATCH] fuse: freezing abort when use wait_event_killable{,_exclusive}().
@ 2016-12-01 5:43 cuilifei
2016-12-02 16:16 ` kbuild test robot
2016-12-02 18:42 ` kbuild test robot
0 siblings, 2 replies; 14+ messages in thread
From: cuilifei @ 2016-12-01 5:43 UTC (permalink / raw)
To: linux-kernel; +Cc: miklos, cuilifei
Freezing process can abort when a client is waiting uninterruptibly
for a response. Add new macro wait_fatal_freezable to try to fix it.
Signed-off-by: cuilifei <cuilifei@xiaomi.com>
---
fs/fuse/dev.c | 47 +++++++++++++++++++++++++++++++++++++++++++----
1 file changed, 43 insertions(+), 4 deletions(-)
diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c
index 70ea57c..40aea7d 100644
--- a/fs/fuse/dev.c
+++ b/fs/fuse/dev.c
@@ -23,6 +23,24 @@
MODULE_ALIAS_MISCDEV(FUSE_MINOR);
MODULE_ALIAS("devname:fuse");
+#define wait_fatal_freezable(wq, condition, exclusive) \
+({ \
+ int __ret = 0; \
+ do { \
+ if (exclusive) \
+ __ret = wait_event_interruptible_exclusive(wq, \
+ condition); \
+ else \
+ __ret = wait_event_interruptible(wq, \
+ condition); \
+ if (!__ret || fatal_signal_pending(current)) \
+ break; \
+ if (!freezing(current)) \
+ continue; \
+ } while (try_to_freeze()); \
+ __ret; \
+})
+
static struct kmem_cache *fuse_req_cachep;
static struct fuse_dev *fuse_get_dev(struct file *file)
@@ -99,6 +117,19 @@ void fuse_request_free(struct fuse_req *req)
kmem_cache_free(fuse_req_cachep, req);
}
+static void block_sigs(sigset_t *oldset)
+{
+ sigset_t mask;
+
+ siginitsetinv(&mask, sigmask(SIGKILL));
+ sigprocmask(SIG_BLOCK, &mask, oldset);
+}
+
+static void restore_sigs(sigset_t *oldset)
+{
+ sigprocmask(SIG_SETMASK, oldset, NULL);
+}
+
void __fuse_get_request(struct fuse_req *req)
{
atomic_inc(&req->count);
@@ -134,13 +165,18 @@ static struct fuse_req *__fuse_get_req(struct fuse_conn *fc, unsigned npages,
bool for_background)
{
struct fuse_req *req;
+ sigset_t oldset;
+ int intr;
int err;
atomic_inc(&fc->num_waiting);
if (fuse_block_alloc(fc, for_background)) {
err = -EINTR;
- if (wait_event_killable_exclusive(fc->blocked_waitq,
- !fuse_block_alloc(fc, for_background)))
+ block_sigs(&oldset);
+ intr = wait_fatal_freezable(fc->blocked_waitq,
+ !fuse_block_alloc(fc, for_background), true);
+ restore_sigs(&oldset);
+ if (intr)
goto out;
}
/* Matches smp_wmb() in fuse_set_initialized() */
@@ -427,9 +463,12 @@ static void request_wait_answer(struct fuse_conn *fc, struct fuse_req *req)
}
if (!test_bit(FR_FORCE, &req->flags)) {
+ sigset_t oldset;
/* Only fatal signals may interrupt this */
- err = wait_event_killable(req->waitq,
- test_bit(FR_FINISHED, &req->flags));
+ block_sigs(&oldset);
+ err = wait_fatal_freezable(req->waitq,
+ test_bit(FR_FINISHED, &req->flags), false);
+ restore_sigs(&oldset);
if (!err)
return;
--
1.9.1
^ permalink raw reply related [flat|nested] 14+ messages in thread
* [PATCH] fuse: freezing abort when use wait_event_killable{,_exclusive}().
@ 2016-12-01 5:37 cuilifei
2016-12-02 14:42 ` kbuild test robot
2016-12-02 14:51 ` kbuild test robot
0 siblings, 2 replies; 14+ messages in thread
From: cuilifei @ 2016-12-01 5:37 UTC (permalink / raw)
To: linux-kernel; +Cc: miklos, cuilifei
Freezing process can abort when a client is waiting uninterruptibly
for a response. Add new macro wait_fatal_freezable to try to fix it.
Signed-off-by: cuilifei <cuilifei@xiaomi.com>
---
fs/fuse/dev.c | 46 ++++++++++++++++++++++++++++++++++++++++++----
1 file changed, 42 insertions(+), 4 deletions(-)
diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c
index 70ea57c..5c63518 100644
--- a/fs/fuse/dev.c
+++ b/fs/fuse/dev.c
@@ -23,6 +23,23 @@
MODULE_ALIAS_MISCDEV(FUSE_MINOR);
MODULE_ALIAS("devname:fuse");
+#define wait_fatal_freezable(wq, condition, exclusive) \
+({ \
+ int __ret = 0; \
+ do { \
+ if (exclusive) \
+ ret = wait_event_interruptible_exclusive(wq, \
+ condition); \
+ else \
+ ret = wait_event_interruptible(wq, condition); \
+ if (!__ret || fatal_signal_pending(current)) \
+ break; \
+ if (!freezing(current)) \
+ continue; \
+ } while (try_to_freeze()); \
+ __ret; \
+})
+
static struct kmem_cache *fuse_req_cachep;
static struct fuse_dev *fuse_get_dev(struct file *file)
@@ -99,6 +116,19 @@ void fuse_request_free(struct fuse_req *req)
kmem_cache_free(fuse_req_cachep, req);
}
+static void block_sigs(sigset_t *oldset)
+{
+ sigset_t mask;
+
+ siginitsetinv(&mask, sigmask(SIGKILL));
+ sigprocmask(SIG_BLOCK, &mask, oldset);
+}
+
+static void restore_sigs(sigset_t *oldset)
+{
+ sigprocmask(SIG_SETMASK, oldset, NULL);
+}
+
void __fuse_get_request(struct fuse_req *req)
{
atomic_inc(&req->count);
@@ -134,13 +164,18 @@ static struct fuse_req *__fuse_get_req(struct fuse_conn *fc, unsigned npages,
bool for_background)
{
struct fuse_req *req;
+ sigset_t oldset;
+ int intr;
int err;
atomic_inc(&fc->num_waiting);
if (fuse_block_alloc(fc, for_background)) {
err = -EINTR;
- if (wait_event_killable_exclusive(fc->blocked_waitq,
- !fuse_block_alloc(fc, for_background)))
+ block_sigs(&oldset);
+ intr = wait_fatal_freezable(fc->blocked_waitq,
+ !fuse_block_alloc(fc, for_background), true);
+ restore_sigs(&oldset);
+ if (intr)
goto out;
}
/* Matches smp_wmb() in fuse_set_initialized() */
@@ -427,9 +462,12 @@ static void request_wait_answer(struct fuse_conn *fc, struct fuse_req *req)
}
if (!test_bit(FR_FORCE, &req->flags)) {
+ sigset_t oldset;
/* Only fatal signals may interrupt this */
- err = wait_event_killable(req->waitq,
- test_bit(FR_FINISHED, &req->flags));
+ block_sigs(&oldset);
+ err = wait_fatal_freezable(req->waitq,
+ test_bit(FR_FINISHED, &req->flags), false);
+ restore_sigs(&oldset);
if (!err)
return;
--
1.9.1
^ permalink raw reply related [flat|nested] 14+ messages in thread
end of thread, other threads:[~2016-12-16 1:35 UTC | newest]
Thread overview: 14+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2016-12-05 3:19 [PATCH] fuse: freezing abort when use wait_event_killable{,_exclusive}() cuilifei
2016-12-06 22:15 ` Rafael J. Wysocki
2016-12-08 6:31 ` 答复: " 崔立飞
2016-12-14 10:09 ` 崔立飞
2016-12-15 22:40 ` Rafael J. Wysocki
2016-12-16 1:34 ` 崔立飞
-- strict thread matches above, loose matches on Subject: below --
2016-12-02 7:26 cuilifei
2016-12-03 8:54 ` kbuild test robot
2016-12-01 5:43 cuilifei
2016-12-02 16:16 ` kbuild test robot
2016-12-02 18:42 ` kbuild test robot
2016-12-01 5:37 cuilifei
2016-12-02 14:42 ` kbuild test robot
2016-12-02 14:51 ` kbuild test robot
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