From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id CBBF333557D; Fri, 5 Jun 2026 17:22:06 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780680127; cv=none; b=FIGSxYR92HSl25m88NWaNg5mbXBBQw52OBY0fISMxFjpJnTTk/MV1dLhjG0QYLWYIGhcqMZ4mX4pyzgUCoV9RSnKe/o+iJtqr8C16wcmNYMo3BncMOFBvbUVNFIDt0gejbSfhGe9AsOgHHS+pjEnnO0tgvPGX8LUnveeWenkn8c= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780680127; c=relaxed/simple; bh=YsXUhudSPG8T39UQWBKyZ2bF9uGV/rt+NJZyR57L5Fk=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=sO+UX2WlRxpA6CbK75FLAW+YyrPi+lyc16A446JTzXscU1prrKeJleHzZ4T3a4Ay7JqK13disLDo1514a8P1u/RZoAPHHkWlL2IzTsgkYbakPZIA8WG4Obxmda0C3b2EUPEmLhnUw+N+USpTq7lqM5c9g6FMy19YLWqN3WZkN9o= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=BRHTcwSL; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="BRHTcwSL" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6DB7A1F00893; Fri, 5 Jun 2026 17:22:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1780680126; bh=pG5SFLXqHSL16ior17lMXeykIDslLb784eO5noWxsxY=; h=Date:Subject:To:Cc:References:From:In-Reply-To; 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 Precedence: bulk X-Mailing-List: linux-api@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: 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 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