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[209.85.220.65]) by mx.google.com with SMTPS id p5sor1238361ljp.3.2019.06.12.23.48.18 for (Google Transport Security); Wed, 12 Jun 2019 23:48:18 -0700 (PDT) Received-SPF: pass (google.com: domain of gorcunov@gmail.com designates 209.85.220.65 as permitted sender) client-ip=209.85.220.65; Authentication-Results: mx.google.com; dkim=pass header.i=@gmail.com header.s=20161025 header.b=nZ7PQjew; spf=pass (google.com: domain of gorcunov@gmail.com designates 209.85.220.65 as permitted sender) smtp.mailfrom=gorcunov@gmail.com; dmarc=pass (p=NONE sp=QUARANTINE dis=NONE) header.from=gmail.com DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=lv9nqSLtCZiZ8ahiodoBv8WyJCmSbiyt0thoq18zE4o=; b=nZ7PQjewhkNFLJJFS9CWkoOR/2SEzVmnFe8JrDQZP9WGcZpfUm4TWzaVR34kqgOkM6 PSejsxPi0NXyf4QlD5sX4JIbnQfXedVnig36j74X1SFYqDWGSabvXNjxjGVLIXkawcuU FLxHCMmbItnJk/+HFhcv2buBYqTCBeda6PFTmID1zVJDHxvH+2FvmDkY//qUdtytA1rY XAU372/eZO1vArF8Nvb3ESlmzJwhIz6vNWOMU+IhBUUih36nYQRORDh23Fhe5qPHSqz9 W5zZSLTxbnEjMPo5VqL3HJlKMAhbO5g/ZW2HDfLWl0duR2ldpc2FeL0NApW675/Lripg kkbA== X-Google-Smtp-Source: APXvYqy6FpZw7RE8ERzs0oPq21ly6eN+8mWADKZTvCK7LLigk9bmBzrjxoFEZnOBRpHWrUPHGL4mfA== X-Received: by 2002:a2e:2c07:: with SMTP id s7mr6057511ljs.44.1560408498002; Wed, 12 Jun 2019 23:48:18 -0700 (PDT) Received: from uranus.localdomain ([5.18.102.224]) by smtp.gmail.com with ESMTPSA id y18sm396934ljh.1.2019.06.12.23.48.17 (version=TLS1_3 cipher=AEAD-AES256-GCM-SHA384 bits=256/256); Wed, 12 Jun 2019 23:48:17 -0700 (PDT) Received: by uranus.localdomain (Postfix, from userid 1000) id D702646019C; Thu, 13 Jun 2019 09:48:16 +0300 (MSK) Date: Thu, 13 Jun 2019 09:48:16 +0300 From: Cyrill Gorcunov To: Andrei Vagin Cc: Konstantin Khlebnikov , linux-mm@kvack.org, Andrew Morton , linux-kernel@vger.kernel.org, Oleg Nesterov , Matthew Wilcox , Michal Hocko , Kirill Tkhai , Michal =?iso-8859-1?Q?Koutn=FD?= , Al Viro , Roman Gushchin , Dmitry Safonov Subject: Re: [PATCH v2 5/6] proc: use down_read_killable mmap_sem for /proc/pid/map_files Message-ID: <20190613064816.GF23535@uranus.lan> References: <156007465229.3335.10259979070641486905.stgit@buzz> <156007493995.3335.9595044802115356911.stgit@buzz> <20190612231426.GA3639@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190612231426.GA3639@gmail.com> User-Agent: Mutt/1.11.3 (2019-02-01) X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Wed, Jun 12, 2019 at 04:14:28PM -0700, Andrei Vagin wrote: > On Sun, Jun 09, 2019 at 01:09:00PM +0300, Konstantin Khlebnikov wrote: > > Do not stuck forever if something wrong. > > Killable lock allows to cleanup stuck tasks and simplifies investigation. > > This patch breaks the CRIU project, because stat() returns EINTR instead > of ENOENT: > > [root@fc24 criu]# stat /proc/self/map_files/0-0 > stat: cannot stat '/proc/self/map_files/0-0': Interrupted system call > > Here is one inline comment with the fix for this issue. > > > > > It seems ->d_revalidate() could return any error (except ECHILD) to > > abort validation and pass error as result of lookup sequence. > > > > Signed-off-by: Konstantin Khlebnikov > > Reviewed-by: Roman Gushchin > > Reviewed-by: Cyrill Gorcunov > > Reviewed-by: Kirill Tkhai > > It was nice to see all four of you in one place :). Holymoly ;) And we all managed to miss this error code. Thanks, Andrew!