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[44.242.192.44]) by smtp.gmail.com with ESMTPSA id 98e67ed59e1d1-3a78e4f3911sm1184151a91.15.2026.10.02.20.31.13 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 02 Oct 2026 20:31:14 -0700 (PDT) From: Ayush Ranjan To: Pedro Falcato Cc: Ayush Ranjan , Hugh Dickins , Matthew Wilcox , Andrew Morton , Jan Kara , Baolin Wang , David Hildenbrand , Gregory Price , linux-mm@kvack.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [BUG] shmem: FALLOC_FL_PUNCH_HOLE vs fault-around race corrupts page cache / rss counters Date: Sat, 3 Oct 2026 03:31:03 +0000 Message-ID: <20261003033107.1488699-1-ayushr@modal.com> X-Mailer: git-send-email 2.52.0 In-Reply-To: <20260925065013.3682431-1-ayushr@modal.com> References: <20260924061708.1645968-1-ayushr@modal.com> <20260925053027.1998394-1-ayushr@modal.com> <20260925065013.3682431-1-ayushr@modal.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Stat-Signature: hrgojt6xiz8qx4qb834odegn44jpkumi X-Rspamd-Queue-Id: 3ECF4140003 X-Rspam-User: X-Rspamd-Server: rspam01 X-HE-Tag: 1790998276-763735 X-HE-Meta: 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 aZ2DZL8K QUrbX5yBroE53LJOOsDrkWcQ3RJDgmVlcc3MAz1WvDMDC+9hr0NsLiy6MqlxIifaPqwinnnQzW/r3UYav6OHB4GPnNiswiHElrEapPBmkwGQ6DOtcpg1e8Irw+Yf8eAjv0GXtP/RkpC1QoCVAwxBLHetfxAztCxbt7oqZryGwjKmd/4tsIJSikjav4kUL5rhjcXPzQ1HKscH4LS3wWI9bsSY6hLSZeLqUmoHrS6CKD+IZJPsUoCR0+Mrc7jRj9k/lXgkTQFWt40w7O0zni/dn9jGplDXJg/Q8m6MJa6kDHOa0t2pWIgmLMerS+e0+sRc0I80MTnaUBVCriYsZMwfjznmhcNChNbpV5h7vXoJTp/5nXoJkZPFxCsOwyEJOGaJlM4KrnAazuRjoSOj1GJEk9QzkDbCsvzt54ToP9roIhXfEYrz+Zpl56AISujIdr2n5gH9xm8A+UMxAy1tmUlYPf2V8Uk0TLkWTm0gRSVyZwMFhnxM= Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: Hi all, Gentle ping on this. The reproducer in my previous mail [1] triggers "Bad page cache ... still mapped when deleted" on 6.18.46 within a couple of minutes on a 128-CPU bare-metal box, with no fork() and no gVisor involved. We continue to hit this in production at low frequency, so I am happy to test patches or collect more data if that would help. Thanks, Ayush [1] https://lore.kernel.org/all/20260925065013.3682431-1-ayushr@modal.com/