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b=NH30Knx/rQBjY70h33pZJsdDa3qAzY4uq/KYKBhUN8qk1pNAQ6F67C81O9jhHv1gS qnp2ajP2p1QLUzjqg/3mdi8PtjgsM/f048oy1RotBnwkU/sUWnoOT2/cYYdLrTBrNQ 8QIyy0ATNhSwGdjtqtXXM8b8uu5GioQYP7E3HCHo= Date: Sun, 3 May 2026 06:23:04 -0700 From: Andrew Morton To: Vineet Agarwal Cc: shuah@kernel.org, linux-kselftest@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, david@kernel.org, ljs@kernel.org, Liam.Howlett@oracle.com, vbabka@kernel.org, rppt@kernel.org, surenb@google.com, mhocko@suse.com Subject: Re: [PATCH v3] selftests/mm: ksm-functional-tests: fix partial write handling Message-Id: <20260503062304.02b166415ef419cf4df6cb87@linux-foundation.org> In-Reply-To: <20260503101229.654763-1-agarwal.vineet2006@gmail.com> References: <20260503101229.654763-1-agarwal.vineet2006@gmail.com> X-Mailer: Sylpheed 3.7.0 (GTK+ 2.24.33; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Rspam-User: X-Rspamd-Server: rspam10 X-Rspamd-Queue-Id: 4C3D940005 X-Stat-Signature: h35wcye7i1x9w4wwnt9xog364iyzna1c X-HE-Tag: 1777814591-41289 X-HE-Meta: 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 lzoDG0t2 S9Bea6UOHG+g5DFZ+t3awDGo2nkhMLz8Ardwgofi36yhG5kwaB4LxrPTYZrHEj6x6+ifaumc90VhutirPeLS3CeFgYfXp5F60wSqV8s7jdZvN0dtTgg1j97i2TDXXFSN8flo4TBp8NJm5YKqhKQGp9nS1+0VFMqMFsmHDeKSNFZSAVPTCGmD8z5tHxl0eLmy59M1u+QCuCRKl4H0r+isC94uICmBmThLsP2Z0sjyPKGesajHMnLyEj0T9//ppLfRKsNXNf4FSYcqO2dUFj0NQ/Ugog7ysFnqHdLjkjBGGb5oOFqKPFqkfbJfiQHQTr5QTT4CyePYZjofUp+4ZSRmlW/+OpmE+ztDRPM++0JgLjrSVNY/yYsIAhKFvzxvcD78D3Oce2sEdktiZkwM+qGWlC8uujg== Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Sun, 3 May 2026 15:38:40 +0530 Vineet Agarwal wrote: > Update write() checks to properly detect and handle partial writes. > > Previously, partial writes (ret > 0 && ret != len) could be treated > as success because write() does not set errno in this case and the > code returned -errno. This could result in returning 0 and > incorrectly signaling success. > > Fix this by verifying that write() returns the full expected length > and treating any mismatch as failure. Thanks. AI review asked some questions: https://sashiko.dev/#/patchset/20260503101229.654763-1-agarwal.vineet2006@gmail.com