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Fri, 29 Nov 2019 09:08:58 +0000 (UTC) Subject: Re: [PATCH v2 6/8] mm: prevent get_user_pages() from overflowing page refcount To: "gregkh@linuxfoundation.org" , Ajay Kaher Cc: "torvalds@linux-foundation.org" , "punit.agrawal@arm.com" , "akpm@linux-foundation.org" , "kirill.shutemov@linux.intel.com" , "willy@infradead.org" , "will.deacon@arm.com" , "mszeredi@redhat.com" , "stable@vger.kernel.org" , "linux-mm@kvack.org" , "linux-kernel@vger.kernel.org" , Srivatsa Bhat , "srivatsa@csail.mit.edu" , Alexey Makhalov , Srinidhi Rao , Vikash Bansal , Anish Swaminathan , Vasavi Sirnapalli , Steven Rostedt , "stable@kernel.org" , Ben Hutchings References: <1570581863-12090-1-git-send-email-akaher@vmware.com> <1570581863-12090-7-git-send-email-akaher@vmware.com> <0E5175FB-7058-4211-9AA4-9D5E2F6A30B9@vmware.com> <35d74931-2c18-00ff-7622-522a79be9103@suse.cz> <88E8A78A-6CA3-46C1-A2AA-DFE7A3A52586@vmware.com> <20191121203823.GE813260@kroah.com> From: Vlastimil Babka Autocrypt: addr=vbabka@suse.cz; prefer-encrypt=mutual; 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Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.2.1 MIME-Version: 1.0 In-Reply-To: <20191121203823.GE813260@kroah.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org On 11/21/19 9:38 PM, gregkh@linuxfoundation.org wrote: > On Mon, Nov 11, 2019 at 05:00:29AM +0000, Ajay Kaher wrote: >> >> On 06/11/19, 2:25 PM, "Vlastimil Babka" wrote: >> >>> On 10/25/19 8:18 AM, Ajay Kaher wrote: >>>> On 17/10/19, 9:58 PM, "Ajay Kaher" wrote: >>>> >>>>> >>>>> Could we handle arch-specific gup.c in different patch sets and >>>>> let these patches to merge to 4.4.y? >>>> >>>> Vlastimil, please suggest if it's fine to merge these patches to 4.4.y >>> >>> I'm not sure if it makes much sense to merge them without the arch-specific gup >>> support, when we're aware that it's missing. >>> >>>> and handle arch-specific gup.c in different patch sets starts from 4.19.y, >>> >>> Actually arch-specific gup.c were removed in 4.13, so it's enough to start from >>> 4.9.y, which I'm going to finally look into. >> >> Yes x86 gup.c is removed. s390 gup.c is present till 4.19, >> so if you are making changes in this file for 4.4.y and 4.9.y, >> then same should be done for 4.14.y and v4.19.y. > > Ok, I have no idea what to do here. I have two different series from > both of you, yet they are different. > > Can you both come up with a series you agree on, and send it to me, with > both of your acks so that I know this is what should be applied? I've > deleted both of your current series from my todo mbox. I started by fixing up [1] 4.9, 4.14 and 4.19 which already got the backport, but without arch-specific gup.c variants. I'll wait for Ajay's feedback for the 4.4 series. [1] https://lore.kernel.org/linux-mm/20191129090351.3507-1-vbabka@suse.cz/ > thanks, > > greg k-h >