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Wong" , Christoph Hellwig , Alexei Starovoitov , Daniel Borkmann , Meta kernel team , bpf@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, syzbot+09b7d050e4806540153d@syzkaller.appspotmail.com, Christoph Hellwig Subject: Re: [PATCH bpf v2] lib/buildid: use __kernel_read() for sleepable context Message-ID: References: <20251218205505.2415840-1-shakeel.butt@linux.dev> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20251218205505.2415840-1-shakeel.butt@linux.dev> X-Rspam-User: X-Rspamd-Queue-Id: C11911C0011 X-Rspamd-Server: rspam04 X-Stat-Signature: 1dcxyqknz5qqupt85d3z58ib7dh8tje9 X-HE-Tag: 1766102151-246685 X-HE-Meta: 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 UFeBMTw7 BabmdyZcbWbzeVEW3chX9SVbzp6A1EZL79cbN6HM9QcyaQ1JdPHbEVguR1ugL+X+ohyNdydH1rpgW0cudu21xeJazdA+G6nj8NhtMO0EFnEbAszaEHinTqlPJT5bOHIouiJGH9IwkVralmGbClbq17RYvVG2nSaWowBGDr1V+KGuCmh6Ja5zAiHNpMTtAoFy6wfW+19Fes50gWNScm4BxoE+8AJ89hoXbwARbCH3RmFwwSwkiPYAGbY37jG+0XPUurg1hZNPNV6EUnSRfUL8R4uGYqI1YzF3fsnf4igcPgZEVxmaSOVaRVJJnIsihRon5l2KyKgADm9IXe1E5R1+bRKpcxT8QdZMyPzfNbyVbbiPx7ugQaZ3Rg569cuAylgfQ24DD1XbD7h4CJkY= 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: List-Subscribe: List-Unsubscribe: On Thu, Dec 18, 2025 at 12:55:05PM -0800, Shakeel Butt wrote: > + do { > + ret = __kernel_read(r->file, buf, sz, &pos); > + if (ret <= 0) { > + r->err = ret ?: -EIO; > + return NULL; > + } > + buf += ret; > + sz -= ret; > + } while (sz > 0); Why are you doing a loop around __kernel_read()? eg kernel_read() does not do a read around __kernel_read(). The callers of kernel_read() don't do a loop either. So what makes you think it needs to have a loop around it?