Re: [PATCH 1/2] mm: fix the racy mm->locked_vm change in

2015-10-01 Thread Hugh Dickins
On Thu, 1 Oct 2015, Oleg Nesterov wrote: > On 09/30, Hugh Dickins wrote: > > > > On Tue, 29 Sep 2015, Oleg Nesterov wrote: > > > > > "mm->locked_vm += grow" and vm_stat_account() in acct_stack_growth() > > > are not safe; multiple threads using the same ->mm can do this at the > > > same time tryin

Re: [PATCH 1/2] mm: fix the racy mm->locked_vm change in

2015-10-01 Thread Oleg Nesterov
On 09/30, Hugh Dickins wrote: > > On Tue, 29 Sep 2015, Oleg Nesterov wrote: > > > "mm->locked_vm += grow" and vm_stat_account() in acct_stack_growth() > > are not safe; multiple threads using the same ->mm can do this at the > > same time trying to expans different vma's under down_read(mmap_sem).

Re: [PATCH 1/2] mm: fix the racy mm->locked_vm change in

2015-09-30 Thread Hugh Dickins
On Tue, 29 Sep 2015, Oleg Nesterov wrote: > "mm->locked_vm += grow" and vm_stat_account() in acct_stack_growth() > are not safe; multiple threads using the same ->mm can do this at the > same time trying to expans different vma's under down_read(mmap_sem). expand > This means

[PATCH 1/2] mm: fix the racy mm->locked_vm change in

2015-09-29 Thread Oleg Nesterov
"mm->locked_vm += grow" and vm_stat_account() in acct_stack_growth() are not safe; multiple threads using the same ->mm can do this at the same time trying to expans different vma's under down_read(mmap_sem). This means that one of the "locked_vm += grow" changes can be lost and we can miss munlock