From: Michal Hocko <mhocko@kernel.org> To: Vlastimil Babka <vbabka@suse.cz> 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>, "Oleg Nesterov" <oleg@redhat.com> Subject: Re: [PATCH 02/18] mm: make vm_mmap killable Date: Fri, 11 Mar 2016 13:12:35 +0100 [thread overview] Message-ID: <20160311121235.GI27701@dhcp22.suse.cz> (raw) In-Reply-To: <56E29702.5030100@suse.cz> On Fri 11-03-16 10:59:30, Vlastimil Babka wrote: > On 02/29/2016 02:26 PM, Michal Hocko wrote: > >From: Michal Hocko <mhocko@suse.com> > > > >All the callers of vm_mmap seem to check for the failure already > >and bail out in one way or another on the error which means that > > Hmm I'm not that sure about this one: > 17 1071 fs/binfmt_elf.c <<load_elf_binary>> > > Assigns result of vm_mmap() to "error" variable which is never checked. Yes it is not checked but not used either. If the current got killed then it wouldn't return to the userspace so my understanding is that not checking this value is not a problem. At least that is my understanding. > Shouldn't __must_check trigger here? well, __must_check is a misleading name. It doesn't actually enforce the value is checked. It just has to be used and an assignment is sufficient. I was discussing this without our gcc guy and he promissed to look and try to come up with a different attribute which would actually work like __must_check. -- Michal Hocko SUSE Labs
WARNING: multiple messages have this Message-ID (diff)
From: Michal Hocko <mhocko@kernel.org> To: Vlastimil Babka <vbabka@suse.cz> 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>, "Oleg Nesterov" <oleg@redhat.com>, "Peter Zijlstra" <peterz@infradead.org>, "Petr Cermak" <petrcermak@chromium.org>, "Thomas Gleixner" <tglx@linutronix.de>, "Al Viro" <viro@zeniv.linux.org.uk> Subject: Re: [PATCH 02/18] mm: make vm_mmap killable Date: Fri, 11 Mar 2016 13:12:35 +0100 [thread overview] Message-ID: <20160311121235.GI27701@dhcp22.suse.cz> (raw) Message-ID: <20160311121235.Pk3mzgsR0xJuOVfgSqOeuuGJg9lY08Rfxp7SM4L8bbE@z> (raw) In-Reply-To: <56E29702.5030100@suse.cz> On Fri 11-03-16 10:59:30, Vlastimil Babka wrote: > On 02/29/2016 02:26 PM, Michal Hocko wrote: > >From: Michal Hocko <mhocko@suse.com> > > > >All the callers of vm_mmap seem to check for the failure already > >and bail out in one way or another on the error which means that > > Hmm I'm not that sure about this one: > 17 1071 fs/binfmt_elf.c <<load_elf_binary>> > > Assigns result of vm_mmap() to "error" variable which is never checked. Yes it is not checked but not used either. If the current got killed then it wouldn't return to the userspace so my understanding is that not checking this value is not a problem. At least that is my understanding. > Shouldn't __must_check trigger here? well, __must_check is a misleading name. It doesn't actually enforce the value is checked. It just has to be used and an assignment is sufficient. I was discussing this without our gcc guy and he promissed to look and try to come up with a different attribute which would actually work like __must_check. -- Michal Hocko SUSE Labs
next prev parent reply other threads:[~2016-03-11 12:12 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 [this message] 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 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=20160311121235.GI27701@dhcp22.suse.cz \ --to=mhocko@kernel.org \ --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=mingo@kernel.org \ --cc=oleg@redhat.com \ --cc=rientjes@google.com \ --cc=vbabka@suse.cz \ /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).