From: Oleg Nesterov <oleg@redhat.com> To: Michal Hocko <mhocko@kernel.org> Cc: LKML <linux-kernel@vger.kernel.org>, "Andrew Morton" <akpm@linux-foundation.org>, linux-mm@kvack.org, "Alex Deucher" <alexander.deucher@amd.com>, "Alex Thorlton" <athorlton@sgi.com>, "Andrea Arcangeli" <aarcange@redhat.com>, "Andy Lutomirski" <luto@amacapital.net>, "Benjamin LaHaise" <bcrl@kvack.org>, "Christian König" <christian.koenig@amd.com>, "Daniel Vetter" <daniel.vetter@intel.com>, "Dave Hansen" <dave.hansen@linux.intel.com>, "David Airlie" <airlied@linux.ie>, "Davidlohr Bueso" <dave@stgolabs.net>, "David Rientjes" <rientjes@google.com>, "H . Peter Anvin" <hpa@zytor.com>, "Hugh Dickins" <hughd@google.com>, "Ingo Molnar" <mingo@kernel.org>, "Johannes Weiner" <hannes@cmpxchg.org>, "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>, "Konstantin Khlebnikov" <koct9i@gmail.com>, linux-arch@vger.kernel.org, "Mel Gorman" <mgorman@suse.de>, "Peter Zijlstra" <peterz@infradead.org> Subject: Re: [PATCH 13/18] exec: make exec path waiting for mmap_sem killable Date: Mon, 29 Feb 2016 19:10:19 +0100 [thread overview] Message-ID: <20160229181018.GF3615@redhat.com> (raw) In-Reply-To: <20160229174739.GL16930@dhcp22.suse.cz> On 02/29, Michal Hocko wrote: > > On Mon 29-02-16 18:23:34, Oleg Nesterov wrote: > > On 02/29, Michal Hocko wrote: > > > > > > @@ -267,7 +267,10 @@ static int __bprm_mm_init(struct linux_binprm *bprm) > > > if (!vma) > > > return -ENOMEM; > > > > > > - down_write(&mm->mmap_sem); > > > + if (down_write_killable(&mm->mmap_sem)) { > > > + err = -EINTR; > > > + goto err_free; > > > + } > > > vma->vm_mm = mm; > > > > I won't argue, but this looks unnecessary. Nobody else can see this new mm, > > down_write() can't block. > > > > In fact I think we can just remove down_write/up_write here. Except perhaps > > there is lockdep_assert_held() somewhere in these paths. > > This is what I had initially but then I've noticed that mm_alloc() does > mm_init(current)->init_new_context(current) yes, and init_new_context() is arch dependant... > code doesn't seem much harder to follow, the callers are already > handling all error paths so I guess it would be better to simply move on > this. Yes, agreed, please forget. Oleg.
WARNING: multiple messages have this Message-ID (diff)
From: Oleg Nesterov <oleg@redhat.com> To: Michal Hocko <mhocko@kernel.org> Cc: LKML <linux-kernel@vger.kernel.org>, "Andrew Morton" <akpm@linux-foundation.org>, linux-mm@kvack.org, "Alex Deucher" <alexander.deucher@amd.com>, "Alex Thorlton" <athorlton@sgi.com>, "Andrea Arcangeli" <aarcange@redhat.com>, "Andy Lutomirski" <luto@amacapital.net>, "Benjamin LaHaise" <bcrl@kvack.org>, "Christian König" <christian.koenig@amd.com>, "Daniel Vetter" <daniel.vetter@intel.com>, "Dave Hansen" <dave.hansen@linux.intel.com>, "David Airlie" <airlied@linux.ie>, "Davidlohr Bueso" <dave@stgolabs.net>, "David Rientjes" <rientjes@google.com>, "H . Peter Anvin" <hpa@zytor.com>, "Hugh Dickins" <hughd@google.com>, "Ingo Molnar" <mingo@kernel.org>, "Johannes Weiner" <hannes@cmpxchg.org>, "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>, "Konstantin Khlebnikov" <koct9i@gmail.com>, linux-arch@vger.kernel.org, "Mel Gorman" <mgorman@suse.de>, "Peter Zijlstra" <peterz@infradead.org>, "Petr Cermak" <petrcermak@chromium.org>, "Thomas Gleixner" <tglx@linutronix.de>, "Alexander Viro" <viro@zeniv.linux.org.uk> Subject: Re: [PATCH 13/18] exec: make exec path waiting for mmap_sem killable Date: Mon, 29 Feb 2016 19:10:19 +0100 [thread overview] Message-ID: <20160229181018.GF3615@redhat.com> (raw) Message-ID: <20160229181019.h-9WSwO_7BtA-d66zeYc9mmMo8PAflBK0ZXUpj4HkMU@z> (raw) In-Reply-To: <20160229174739.GL16930@dhcp22.suse.cz> On 02/29, Michal Hocko wrote: > > On Mon 29-02-16 18:23:34, Oleg Nesterov wrote: > > On 02/29, Michal Hocko wrote: > > > > > > @@ -267,7 +267,10 @@ static int __bprm_mm_init(struct linux_binprm *bprm) > > > if (!vma) > > > return -ENOMEM; > > > > > > - down_write(&mm->mmap_sem); > > > + if (down_write_killable(&mm->mmap_sem)) { > > > + err = -EINTR; > > > + goto err_free; > > > + } > > > vma->vm_mm = mm; > > > > I won't argue, but this looks unnecessary. Nobody else can see this new mm, > > down_write() can't block. > > > > In fact I think we can just remove down_write/up_write here. Except perhaps > > there is lockdep_assert_held() somewhere in these paths. > > This is what I had initially but then I've noticed that mm_alloc() does > mm_init(current)->init_new_context(current) yes, and init_new_context() is arch dependant... > code doesn't seem much harder to follow, the callers are already > handling all error paths so I guess it would be better to simply move on > this. Yes, agreed, please forget. Oleg.
next prev parent reply other threads:[~2016-02-29 18:10 UTC|newest] Thread overview: 138+ messages / expand[flat|nested] mbox.gz Atom feed top 2016-02-29 13:26 [PATCH 0/18] change mmap_sem taken for write killable Michal Hocko 2016-02-29 13:26 ` Michal Hocko 2016-02-29 13:26 ` [PATCH 01/18] mm: Make mmap_sem for write waits killable for mm syscalls Michal Hocko 2016-02-29 13:26 ` Michal Hocko 2016-02-29 13:44 ` kbuild test robot 2016-02-29 13:44 ` kbuild test robot 2016-02-29 13:44 ` kbuild test robot 2016-02-29 13:44 ` kbuild test robot 2016-03-10 15:47 ` Vlastimil Babka 2016-03-10 15:47 ` Vlastimil Babka 2016-03-10 15:56 ` Michal Hocko 2016-03-10 15:56 ` Michal Hocko 2016-02-29 13:26 ` [PATCH 02/18] mm: make vm_mmap killable Michal Hocko 2016-02-29 13:26 ` Michal Hocko 2016-03-11 9:59 ` Vlastimil Babka 2016-03-11 9:59 ` Vlastimil Babka 2016-03-11 12:12 ` Michal Hocko 2016-03-11 12:12 ` Michal Hocko 2016-03-11 12:43 ` Vlastimil Babka 2016-03-11 12:43 ` Vlastimil Babka 2016-03-11 12:55 ` Michal Hocko 2016-03-11 12:55 ` Michal Hocko 2016-02-29 13:26 ` [PATCH 03/18] mm: make vm_munmap killable Michal Hocko 2016-02-29 13:26 ` Michal Hocko 2016-03-11 10:06 ` Vlastimil Babka 2016-03-11 10:06 ` Vlastimil Babka 2016-03-11 12:32 ` Michal Hocko 2016-03-11 12:32 ` Michal Hocko 2016-02-29 13:26 ` [PATCH 04/18] mm, aout: handle vm_brk failures Michal Hocko 2016-02-29 13:26 ` Michal Hocko 2016-03-11 10:32 ` Vlastimil Babka 2016-03-11 10:32 ` Vlastimil Babka 2016-03-11 12:42 ` Michal Hocko 2016-03-11 12:42 ` Michal Hocko 2016-02-29 13:26 ` [PATCH 05/18] mm, elf: handle vm_brk error Michal Hocko 2016-02-29 13:26 ` Michal Hocko 2016-03-11 10:35 ` Vlastimil Babka 2016-03-11 10:35 ` Vlastimil Babka 2016-02-29 13:26 ` [PATCH 06/18] mm: make vm_brk killable Michal Hocko 2016-02-29 13:26 ` Michal Hocko 2016-03-11 10:44 ` Vlastimil Babka 2016-03-11 10:44 ` Vlastimil Babka 2016-02-29 13:26 ` [PATCH 07/18] mm, proc: make clear_refs killable Michal Hocko 2016-02-29 13:26 ` Michal Hocko 2016-02-29 13:47 ` kbuild test robot 2016-02-29 13:47 ` kbuild test robot 2016-02-29 17:38 ` Oleg Nesterov 2016-02-29 17:38 ` Oleg Nesterov 2016-02-29 17:53 ` Michal Hocko 2016-02-29 17:53 ` Michal Hocko 2016-02-29 17:58 ` Oleg Nesterov 2016-02-29 17:58 ` Oleg Nesterov 2016-02-29 18:02 ` Michal Hocko 2016-02-29 18:02 ` Michal Hocko 2016-02-29 13:26 ` [PATCH 08/18] mm, fork: make dup_mmap wait for mmap_sem for write killable Michal Hocko 2016-02-29 13:26 ` Michal Hocko 2016-02-29 13:48 ` kbuild test robot 2016-02-29 13:48 ` kbuild test robot 2016-02-29 17:54 ` Oleg Nesterov 2016-02-29 17:54 ` Oleg Nesterov 2016-02-29 13:26 ` [PATCH 09/18] ipc, shm: make shmem attach/detach wait for mmap_sem killable Michal Hocko 2016-02-29 13:26 ` Michal Hocko 2016-03-08 19:15 ` Davidlohr Bueso 2016-03-08 19:15 ` Davidlohr Bueso 2016-03-09 10:16 ` Michal Hocko 2016-03-09 10:16 ` Michal Hocko 2016-02-29 13:26 ` [PATCH 10/18] vdso: make arch_setup_additional_pages wait for mmap_sem for write killable Michal Hocko 2016-02-29 13:26 ` Michal Hocko 2016-02-29 13:45 ` kbuild test robot 2016-02-29 13:45 ` kbuild test robot 2016-02-29 13:50 ` kbuild test robot 2016-02-29 13:50 ` kbuild test robot 2016-02-29 13:53 ` kbuild test robot 2016-02-29 13:53 ` kbuild test robot 2016-02-29 15:41 ` Andy Lutomirski 2016-02-29 15:41 ` Andy Lutomirski 2016-03-11 11:28 ` Vlastimil Babka 2016-03-11 11:28 ` Vlastimil Babka 2016-02-29 13:26 ` [PATCH 11/18] coredump: make coredump_wait wait for mma_sem " Michal Hocko 2016-02-29 13:26 ` Michal Hocko 2016-02-29 15:57 ` Oleg Nesterov 2016-02-29 15:57 ` Oleg Nesterov 2016-03-11 11:32 ` Vlastimil Babka 2016-03-11 11:32 ` Vlastimil Babka 2016-03-11 11:54 ` Vlastimil Babka 2016-03-11 11:54 ` Vlastimil Babka 2016-03-11 12:46 ` Michal Hocko 2016-03-11 12:46 ` Michal Hocko 2016-02-29 13:26 ` [PATCH 12/18] aio: make aio_setup_ring killable Michal Hocko 2016-02-29 13:26 ` Michal Hocko 2016-02-29 16:17 ` Jeff Moyer 2016-02-29 16:17 ` Jeff Moyer 2016-03-11 11:57 ` Vlastimil Babka 2016-03-11 11:57 ` Vlastimil Babka 2016-02-29 13:26 ` [PATCH 13/18] exec: make exec path waiting for mmap_sem killable Michal Hocko 2016-02-29 13:26 ` Michal Hocko 2016-02-29 17:23 ` Oleg Nesterov 2016-02-29 17:23 ` Oleg Nesterov 2016-02-29 17:47 ` Michal Hocko 2016-02-29 17:47 ` Michal Hocko 2016-02-29 18:10 ` Oleg Nesterov [this message] 2016-02-29 18:10 ` Oleg Nesterov 2016-03-11 12:51 ` Vlastimil Babka 2016-03-11 12:51 ` Vlastimil Babka 2016-02-29 13:26 ` [PATCH 14/18] prctl: make PR_SET_THP_DISABLE wait " Michal Hocko 2016-02-29 13:26 ` Michal Hocko 2016-03-11 12:54 ` Vlastimil Babka 2016-03-11 12:54 ` Vlastimil Babka 2016-02-29 13:26 ` [PATCH 15/18] uprobes: wait for mmap_sem for write killable Michal Hocko 2016-02-29 13:26 ` Michal Hocko 2016-02-29 15:57 ` Oleg Nesterov 2016-02-29 15:57 ` Oleg Nesterov 2016-02-29 16:28 ` Michal Hocko 2016-02-29 16:28 ` Michal Hocko 2016-02-29 17:12 ` Oleg Nesterov 2016-02-29 17:12 ` Oleg Nesterov 2016-02-29 13:26 ` [PATCH 16/18] drm/i915: make i915_gem_mmap_ioctl wait for mmap_sem killable Michal Hocko 2016-02-29 13:26 ` Michal Hocko 2016-03-11 15:23 ` Vlastimil Babka 2016-03-11 15:23 ` Vlastimil Babka 2016-02-29 13:26 ` [PATCH 17/18] drm/radeon: make radeon_mn_get " Michal Hocko 2016-02-29 13:26 ` Michal Hocko 2016-02-29 13:35 ` Christian König 2016-02-29 13:35 ` Christian König 2016-03-11 15:27 ` Vlastimil Babka 2016-03-11 15:27 ` Vlastimil Babka 2016-02-29 13:26 ` [PATCH 18/18] drm/amdgpu: make amdgpu_mn_get " Michal Hocko 2016-02-29 13:26 ` Michal Hocko 2016-03-11 15:29 ` Vlastimil Babka 2016-03-11 15:29 ` Vlastimil Babka 2016-02-29 13:31 ` [PATCH 0/18] change mmap_sem taken for write killable Michal Hocko 2016-02-29 13:31 ` Michal Hocko 2016-02-29 14:04 ` Kirill A. Shutemov 2016-02-29 14:04 ` Kirill A. Shutemov 2016-02-29 14:16 ` Michal Hocko 2016-02-29 14:16 ` Michal Hocko 2016-02-29 15:03 ` Kirill A. Shutemov 2016-02-29 15:03 ` Kirill A. Shutemov
Reply instructions: You may reply publicly to this message via plain-text email using any one of the following methods: * Save the following mbox file, import it into your mail client, and reply-to-all from there: mbox Avoid top-posting and favor interleaved quoting: https://en.wikipedia.org/wiki/Posting_style#Interleaved_style * Reply using the --to, --cc, and --in-reply-to switches of git-send-email(1): git send-email \ --in-reply-to=20160229181018.GF3615@redhat.com \ --to=oleg@redhat.com \ --cc=aarcange@redhat.com \ --cc=airlied@linux.ie \ --cc=akpm@linux-foundation.org \ --cc=alexander.deucher@amd.com \ --cc=athorlton@sgi.com \ --cc=bcrl@kvack.org \ --cc=christian.koenig@amd.com \ --cc=daniel.vetter@intel.com \ --cc=dave.hansen@linux.intel.com \ --cc=dave@stgolabs.net \ --cc=hannes@cmpxchg.org \ --cc=hpa@zytor.com \ --cc=hughd@google.com \ --cc=kirill.shutemov@linux.intel.com \ --cc=koct9i@gmail.com \ --cc=linux-arch@vger.kernel.org \ --cc=linux-kernel@vger.kernel.org \ --cc=linux-mm@kvack.org \ --cc=luto@amacapital.net \ --cc=mgorman@suse.de \ --cc=mhocko@kernel.org \ --cc=mingo@kernel.org \ --cc=peterz@infradead.org \ --cc=rientjes@google.com \ /path/to/YOUR_REPLY https://kernel.org/pub/software/scm/git/docs/git-send-email.html * If your mail client supports setting the In-Reply-To header via mailto: links, try the mailto: linkBe sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions for how to clone and mirror all data and code used for this inbox; as well as URLs for NNTP newsgroup(s).