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b=BRHTcwSLuouyHkitWoP16Un5boWNOPQuWBN7Wfs4c5kaxEYJ5pzQ8IC76YLhWwEJE MfOCyBaL2kAydrKWSApqqYLHEBWPHcaG4eDe30unadQuD6RcUvfa2vw1+2Za984I1O T6ebBHPw/pq0y5QyWi1323ELh9Tqq83f7wYypIDpQfPGzm5O5Feudng6r7ZlPyLaSm iBmmGcoRUVYnsCXsjWiFykWgBHb6b1neceY1xFS8zkQoVWE9SpVL7uBRM6AhpnN+vm LfrXK+Y4iyvFm+H/zZQ+YWgb+mpoBjGJ6KpuRXcgpszyIIooSDNHVSCiPTBqfk+fs9 RL6Kk8Jp0ZBLw== Message-ID: Date: Fri, 5 Jun 2026 19:21:58 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 2/3] vmsplice: make vmsplice a trivial wrapper for preadv2/pwritev2 To: Mark Brown , Linus Torvalds Cc: Askar Safin , linux-fsdevel@vger.kernel.org, Christian Brauner , Alexander Viro , Jan Kara , linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-api@vger.kernel.org, netdev@vger.kernel.org, Matthew Wilcox , Jens Axboe , Christoph Hellwig , David Howells , Andrew Morton , Pedro Falcato , Aishwharya.TCV@arm.com, ltp@lists.linux.it, Miklos Szeredi , patches@lists.linux.dev References: <20260531010107.1953702-1-safinaskar@gmail.com> <20260531010107.1953702-3-safinaskar@gmail.com> <1eac3b42-5dde-41c4-930a-d74cda9e6d68@sirena.org.uk> From: "David Hildenbrand (Arm)" Content-Language: en-US Autocrypt: addr=david@kernel.org; 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charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: 9ADBDA000D X-Rspam-User: X-Stat-Signature: um3aw4ftqci7tu9mn97e88iyqpw6f5y5 X-Rspamd-Server: rspam08 X-HE-Tag: 1780680127-50081 X-HE-Meta: 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 UIvNUw+O JP9l4eLZ2MhJuSR0IwXQt5NcpsKNNrrSiMM28+eRklmIjcGT6Pkdbh5IrqP4HhQjoOJA/Wu2fnAD2BpWK2kMTL/vCZ5IAWqDEQiwjVSY2+pY8FYsW29QbkhGhNEJCCxg/EYCYbdBIJaghivH7qtMro9z5Wu8u2QuAXdGopk66nbOAy/+PcD1qW/ivB50ZLSQSF6jsv3/eeR4S682iR9VWa0vq3WRLIV1agVI+UfnAszLKnstD0Dy6XO3I0lcO/dNcmsrNFN2Clrk21x4Axbxp3dclYYtgZjcMQWr5 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 6/5/26 18:26, Mark Brown wrote: > On Fri, Jun 05, 2026 at 09:02:52AM -0700, Linus Torvalds wrote: >> On Fri, 5 Jun 2026 at 04:02, Mark Brown wrote: > >>> | L4472tst_test.c:2050: TINFO: Tested kernel: 7.1.0-rc6-next-20260604 #1 SMP @1780589917 armv7l >>> | L4473tst_kconfig.c:71: TINFO: Couldn't locate kernel config! >>> | L4474tst_test.c:1875: TINFO: Overall timeout per run is 0h 00m 30s > >> I htink this is the same thing that Christian already noted (he said >> "reported by David", but I don't know which David ;), where the >> vmsplice() writev() emulation was done as a blocking write, even >> though vmsplice only blocked at the beginning (ie waiting only for >> _initial_ space to write, not then blocking afterwards). > > Ah, yes it is - exactly the same issue that's mentioned in[1], I missed > it in the middle of the quite large thread and didn't directly find > David's report. Sorry for the duplication there. Yeah, I quickly discussed this with Christian on a different channel and he ended up sharing the report with the analysis directly. -- Cheers, David