Re: [PATCH V2] mm, memory_failure: don't send BUS_MCEERR_AO for action required error
On Sat, May 30, 2020 at 09:08:43AM +0200, Pankaj Gupta wrote:
> > Some processes dont't want to be killed early, but in "Action Required"
> > case, those also may be killed by BUS_MCEERR_AO when sharing memory
> > with other which is accessing the fail memory.
> > And sending SIGBUS with BUS_MCEERR_AO for action required error is
> > strange, so ignore the non-current processes here.
> >
> > Suggested-by: Naoya Horiguchi
> > Signed-off-by: Wetp Zhang
> > ---
> > mm/memory-failure.c | 15 +--
> > 1 file changed, 9 insertions(+), 6 deletions(-)
> >
> > diff --git a/mm/memory-failure.c b/mm/memory-failure.c
> > index a96364be8ab4..dd3862fcf2e9 100644
> > --- a/mm/memory-failure.c
> > +++ b/mm/memory-failure.c
> > @@ -210,14 +210,17 @@ static int kill_proc(struct to_kill *tk, unsigned
> > long pfn, int flags)
> > {
> > struct task_struct *t = tk->tsk;
> > short addr_lsb = tk->size_shift;
> > - int ret;
> > + int ret = 0;
> >
> > - pr_err("Memory failure: %#lx: Sending SIGBUS to %s:%d due to
> > hardware memory corruption\n",
> > - pfn, t->comm, t->pid);
> > + if ((t->mm == current->mm) || !(flags & MF_ACTION_REQUIRED))
> > + pr_err("Memory failure: %#lx: Sending SIGBUS to %s:%d due
> > to hardware memory corruption\n",
> > + pfn, t->comm, t->pid);
>
> Maybe we can generalize the message condition for better readability.
> Thought a bit but did not get any other idea.
This odd condition might imply that we could have better fix in
task_early_kill(), but that should come after fixing priority issue of
early-kill flag, so let's go with this fix for now.
> >
> > - if ((flags & MF_ACTION_REQUIRED) && t->mm == current->mm) {
> > - ret = force_sig_mceerr(BUS_MCEERR_AR, (void __user
> > *)tk->addr,
> > - addr_lsb);
> > + if (flags & MF_ACTION_REQUIRED) {
> > + if (t->mm == current->mm)
> > + ret = force_sig_mceerr(BUS_MCEERR_AR,
> > +(void __user *)tk->addr, addr_lsb);
> > + /* send no signal to non-current processes */
> > } else {
> > /*
> > * Don't use force here, it's convenient if the signal
> > --
>
> Looks good to me.
> Acked-by: Pankaj Gupta
Thanks!
Acked-by: Naoya Horiguchi
Re: [PATCH V2] mm, memory_failure: don't send BUS_MCEERR_AO for action required error
> Some processes dont't want to be killed early, but in "Action Required"
> case, those also may be killed by BUS_MCEERR_AO when sharing memory
> with other which is accessing the fail memory.
> And sending SIGBUS with BUS_MCEERR_AO for action required error is
> strange, so ignore the non-current processes here.
>
> Suggested-by: Naoya Horiguchi
> Signed-off-by: Wetp Zhang
> ---
> mm/memory-failure.c | 15 +--
> 1 file changed, 9 insertions(+), 6 deletions(-)
>
> diff --git a/mm/memory-failure.c b/mm/memory-failure.c
> index a96364be8ab4..dd3862fcf2e9 100644
> --- a/mm/memory-failure.c
> +++ b/mm/memory-failure.c
> @@ -210,14 +210,17 @@ static int kill_proc(struct to_kill *tk, unsigned long
> pfn, int flags)
> {
> struct task_struct *t = tk->tsk;
> short addr_lsb = tk->size_shift;
> - int ret;
> + int ret = 0;
>
> - pr_err("Memory failure: %#lx: Sending SIGBUS to %s:%d due to hardware
> memory corruption\n",
> - pfn, t->comm, t->pid);
> + if ((t->mm == current->mm) || !(flags & MF_ACTION_REQUIRED))
> + pr_err("Memory failure: %#lx: Sending SIGBUS to %s:%d due to
> hardware memory corruption\n",
> + pfn, t->comm, t->pid);
Maybe we can generalize the message condition for better readability.
Thought a bit but did not get any other idea.
>
> - if ((flags & MF_ACTION_REQUIRED) && t->mm == current->mm) {
> - ret = force_sig_mceerr(BUS_MCEERR_AR, (void __user *)tk->addr,
> - addr_lsb);
> + if (flags & MF_ACTION_REQUIRED) {
> + if (t->mm == current->mm)
> + ret = force_sig_mceerr(BUS_MCEERR_AR,
> +(void __user *)tk->addr, addr_lsb);
> + /* send no signal to non-current processes */
> } else {
> /*
> * Don't use force here, it's convenient if the signal
> --
Looks good to me.
Acked-by: Pankaj Gupta
[PATCH V2] mm, memory_failure: don't send BUS_MCEERR_AO for action required error
Some processes dont't want to be killed early, but in "Action Required"
case, those also may be killed by BUS_MCEERR_AO when sharing memory
with other which is accessing the fail memory.
And sending SIGBUS with BUS_MCEERR_AO for action required error is
strange, so ignore the non-current processes here.
Suggested-by: Naoya Horiguchi
Signed-off-by: Wetp Zhang
---
mm/memory-failure.c | 15 +--
1 file changed, 9 insertions(+), 6 deletions(-)
diff --git a/mm/memory-failure.c b/mm/memory-failure.c
index a96364be8ab4..dd3862fcf2e9 100644
--- a/mm/memory-failure.c
+++ b/mm/memory-failure.c
@@ -210,14 +210,17 @@ static int kill_proc(struct to_kill *tk, unsigned long
pfn, int flags)
{
struct task_struct *t = tk->tsk;
short addr_lsb = tk->size_shift;
- int ret;
+ int ret = 0;
- pr_err("Memory failure: %#lx: Sending SIGBUS to %s:%d due to hardware
memory corruption\n",
- pfn, t->comm, t->pid);
+ if ((t->mm == current->mm) || !(flags & MF_ACTION_REQUIRED))
+ pr_err("Memory failure: %#lx: Sending SIGBUS to %s:%d due to
hardware memory corruption\n",
+ pfn, t->comm, t->pid);
- if ((flags & MF_ACTION_REQUIRED) && t->mm == current->mm) {
- ret = force_sig_mceerr(BUS_MCEERR_AR, (void __user *)tk->addr,
- addr_lsb);
+ if (flags & MF_ACTION_REQUIRED) {
+ if (t->mm == current->mm)
+ ret = force_sig_mceerr(BUS_MCEERR_AR,
+(void __user *)tk->addr, addr_lsb);
+ /* send no signal to non-current processes */
} else {
/*
* Don't use force here, it's convenient if the signal
--
2.14.3 (Apple Git-98)
