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[67.216.200.102]) by smtp.gmail.com with ESMTPSA id 5a478bee46e88-36a42952e1csm25828235eec.20.2026.10.31.23.28.43 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 31 Oct 2026 23:28:45 -0700 (PDT) From: Cheng Yongkang To: Qu Wenruo Cc: Cheng Yongkang , David Sterba , Chris Mason , linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] btrfs: reject refs=0 subvolume without DEAD in SUBVOL_SYNC_WAIT Date: Sat, 31 Oct 2026 23:28:39 -0700 Message-Id: <20261101062839.1747239-1-teel4res@gmail.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: References: <20261025180258.349175-1-teel4res@gmail.com> X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Hi Qu, Thanks for pointing out the failed-delete path. v2 is here: https://lore.kernel.org/linux-btrfs/20261101062539.1744605-1-teel4res@gmail.com/ Before waiting for a deleted subvolume, it now returns -EROFS if the filesystem is read-only. The check runs on every iteration, so it also covers a filesystem that becomes read-only during the wait. On a writable filesystem, a zero-reference root without DEAD returns -EUCLEAN, with unlikely(). Subvolumes that were not deleted or do not exist still return -EEXIST and -ENOENT. Thanks, Cheng Yongkang