From nobody Thu Dec 18 19:25:05 2025 Received: from mail-ej1-f41.google.com (mail-ej1-f41.google.com [209.85.218.41]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 5B4EF13E41D for ; Mon, 29 Jul 2024 09:28:34 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.218.41 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1722245317; cv=none; b=bJCrlf3OgIkhb0TqVwsTyaAdZYZ6W2r1f0fQnqk55ImpOnNKQSUfaaTOz98vCBoude/nDQkt6ssy5KoID4QS65Glub9RvT0PWCTqL5XINB4Ym7OQW1jeys+NO6rOxoyOOWBqzjQMW4NP0FVP/ZgTiuzxwvE0QhpssImDrST/dlU= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1722245317; c=relaxed/simple; bh=KZWJF5oSY7HJ23Uf34KCCrdaHErkdUmBfHVE1m4vszo=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=geHNVichyyYFXRw56sa1puLQvp3UAL//CBoxyyAUoKNcSJnAOQT6iZxeQOy5QjvfarPmXrbI/jRMqSoVge7DxlqE4rQm47iWBkFxMIOFYf/WWAMurqzNT3qw5L2zQEBKfQGeJCVi8ZnCVExPOeG60thS+IHV1RLCgKE5c/AifBs= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=ionos.com; spf=pass smtp.mailfrom=ionos.com; dkim=pass (2048-bit key) header.d=ionos.com header.i=@ionos.com header.b=NuKJXL9P; arc=none smtp.client-ip=209.85.218.41 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=ionos.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=ionos.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=ionos.com header.i=@ionos.com header.b="NuKJXL9P" Received: by mail-ej1-f41.google.com with SMTP id a640c23a62f3a-a7aa4bf4d1eso441808066b.0 for ; Mon, 29 Jul 2024 02:28:34 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ionos.com; s=google; t=1722245313; x=1722850113; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date:message-id:reply-to; bh=Zb9VzgX66ul+EUSAfUjFvHjvcVAUBg0+FBC33/4bxE4=; b=NuKJXL9PUu19RA3lXpYTqEgBSLFaSmKIw0KtxJT1+EPhlf+9dpsl500OEbmyo+MvUr y1b4XV11/0sYA+1y6v2ZypdQF1rsCPlQa7NeBmzFpVyoDd0ON9WtplJ6h22CCwzkNT3d VgMNXqdCsXohAmaenS6Noi8h9ycuAIOOb9r5nzsP8xxFE++zOZro3Z2v44bruptoHXwo cVjfzcS4DfmvcrXbXfOvJpAcdZ0LXCUUcu14HMbZz6ZHV+uFSbMJclPScfgsNmLerIdn jkuMdANWJfBSWVmj6abVi8Q+UgL4eagHPjc3meFdPKVdKWFy2Vrv7Z+fyLb1sFVGwtjB k7Dg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1722245313; x=1722850113; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=Zb9VzgX66ul+EUSAfUjFvHjvcVAUBg0+FBC33/4bxE4=; b=OEv1nEx3sDBQduqIqqs0kO1Ud0SJwP09xyw58zlsPJhy9lrCI8C+k0zVY9KsUWdXnI cbSzkrZk3mtIfoviuShL5in18/K37SN9N4U7AqrcK0eag+t57kzdCFdUxZI3qxMBlRFy 0LGt5AmedsASFb2K8lGSsJsCc0TQPQNvnQH/w/kAvAppqJB98qZyidxoGe4zh67C14eO LM7t7DfuYGRAs5+yAFKVvMxfSIMRpG9NEOSTnWF0ZZVZbHI4UOLj7T3aB7449b9Ppn6z Bj16ezlvjPa2t9fdazYG4s2GaJNPidIzwo4UfsnXHpA936CD9qdv6KOICgBiW/zZnE+8 WBnA== X-Forwarded-Encrypted: i=1; AJvYcCWYQ8F+hJP/0z4LfMOiVFpUhrB3kcjB8lYJtggMOUUeoF3BLue80rxO1fVLdflxrMPxX7BzloVhF8Dp2gyGgia4bRPyh4CaplR8KjkT X-Gm-Message-State: AOJu0Yz7tBMJXP35C5UQ80LwBBNfqz1VQD257AEC2AibfZIOYoBD6u/A zYz5w10qVdLjuCkKKpIczJEuEGKSAp3l5lflk8Raf3OFMlqHZfqEiodAmX8xKPE= X-Google-Smtp-Source: AGHT+IF28YDU5y/QrxYQDHg2q9k8RB4sAVv0+DO2KSJGo95MGgcxetSe963dDXT1fw3tAw3zcm81yg== X-Received: by 2002:a17:907:1c19:b0:a7a:ab8a:380 with SMTP id a640c23a62f3a-a7d40145821mr598571666b.69.1722245312585; Mon, 29 Jul 2024 02:28:32 -0700 (PDT) Received: from raven.intern.cm-ag (p200300dc6f03cd00023064fffe740809.dip0.t-ipconnect.de. [2003:dc:6f03:cd00:230:64ff:fe74:809]) by smtp.gmail.com with ESMTPSA id a640c23a62f3a-a7acad4ae4dsm479944366b.136.2024.07.29.02.28.31 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 29 Jul 2024 02:28:32 -0700 (PDT) From: Max Kellermann To: dhowells@redhat.com, jlayton@kernel.org Cc: willy@infradead.org, linux-cachefs@redhat.com, linux-fsdevel@vger.kernel.org, ceph-devel@vger.kernel.org, linux-kernel@vger.kernel.org, stable@vger.kernel.org, Max Kellermann Subject: [PATCH v2] fs/netfs/fscache_io: remove the obsolete "using_pgpriv2" flag Date: Mon, 29 Jul 2024 11:28:28 +0200 Message-ID: <20240729092828.857383-1-max.kellermann@ionos.com> X-Mailer: git-send-email 2.43.0 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" This fixes a crash bug caused by commit ae678317b95e ("netfs: Remove deprecated use of PG_private_2 as a second writeback flag") by removing a leftover folio_end_private_2() call after all calls to folio_start_private_2() had been removed by the commit. By calling folio_end_private_2() without folio_start_private_2(), the folio refcounter breaks and causes trouble like RCU stalls and general protection faults. Cc: stable@vger.kernel.org Fixes: ae678317b95e ("netfs: Remove deprecated use of PG_private_2 as a sec= ond writeback flag") Link: https://lore.kernel.org/ceph-devel/CAKPOu+_DA8XiMAA2ApMj7Pyshve_YWknw= 8Hdt1=3DzCy9Y87R1qw@mail.gmail.com/ Signed-off-by: Max Kellermann --- fs/ceph/addr.c | 2 +- fs/netfs/fscache_io.c | 29 +---------------------------- include/linux/fscache.h | 30 ++++-------------------------- 3 files changed, 6 insertions(+), 55 deletions(-) diff --git a/fs/ceph/addr.c b/fs/ceph/addr.c index 8c16bc5250ef..485cbd1730d1 100644 --- a/fs/ceph/addr.c +++ b/fs/ceph/addr.c @@ -512,7 +512,7 @@ static void ceph_fscache_write_to_cache(struct inode *i= node, u64 off, u64 len, b struct fscache_cookie *cookie =3D ceph_fscache_cookie(ci); =20 fscache_write_to_cache(cookie, inode->i_mapping, off, len, i_size_read(in= ode), - ceph_fscache_write_terminated, inode, true, caching); + ceph_fscache_write_terminated, inode, caching); } #else static inline void ceph_fscache_write_to_cache(struct inode *inode, u64 of= f, u64 len, bool caching) diff --git a/fs/netfs/fscache_io.c b/fs/netfs/fscache_io.c index 38637e5c9b57..0d8f3f646598 100644 --- a/fs/netfs/fscache_io.c +++ b/fs/netfs/fscache_io.c @@ -166,30 +166,10 @@ struct fscache_write_request { loff_t start; size_t len; bool set_bits; - bool using_pgpriv2; netfs_io_terminated_t term_func; void *term_func_priv; }; =20 -void __fscache_clear_page_bits(struct address_space *mapping, - loff_t start, size_t len) -{ - pgoff_t first =3D start / PAGE_SIZE; - pgoff_t last =3D (start + len - 1) / PAGE_SIZE; - struct page *page; - - if (len) { - XA_STATE(xas, &mapping->i_pages, first); - - rcu_read_lock(); - xas_for_each(&xas, page, last) { - folio_end_private_2(page_folio(page)); - } - rcu_read_unlock(); - } -} -EXPORT_SYMBOL(__fscache_clear_page_bits); - /* * Deal with the completion of writing the data to the cache. */ @@ -198,10 +178,6 @@ static void fscache_wreq_done(void *priv, ssize_t tran= sferred_or_error, { struct fscache_write_request *wreq =3D priv; =20 - if (wreq->using_pgpriv2) - fscache_clear_page_bits(wreq->mapping, wreq->start, wreq->len, - wreq->set_bits); - if (wreq->term_func) wreq->term_func(wreq->term_func_priv, transferred_or_error, was_async); @@ -214,7 +190,7 @@ void __fscache_write_to_cache(struct fscache_cookie *co= okie, loff_t start, size_t len, loff_t i_size, netfs_io_terminated_t term_func, void *term_func_priv, - bool using_pgpriv2, bool cond) + bool cond) { struct fscache_write_request *wreq; struct netfs_cache_resources *cres; @@ -232,7 +208,6 @@ void __fscache_write_to_cache(struct fscache_cookie *co= okie, wreq->mapping =3D mapping; wreq->start =3D start; wreq->len =3D len; - wreq->using_pgpriv2 =3D using_pgpriv2; wreq->set_bits =3D cond; wreq->term_func =3D term_func; wreq->term_func_priv =3D term_func_priv; @@ -260,8 +235,6 @@ void __fscache_write_to_cache(struct fscache_cookie *co= okie, abandon_free: kfree(wreq); abandon: - if (using_pgpriv2) - fscache_clear_page_bits(mapping, start, len, cond); if (term_func) term_func(term_func_priv, ret, false); } diff --git a/include/linux/fscache.h b/include/linux/fscache.h index 9de27643607f..f8c52bddaa15 100644 --- a/include/linux/fscache.h +++ b/include/linux/fscache.h @@ -177,8 +177,7 @@ void __fscache_write_to_cache(struct fscache_cookie *co= okie, loff_t start, size_t len, loff_t i_size, netfs_io_terminated_t term_func, void *term_func_priv, - bool using_pgpriv2, bool cond); -extern void __fscache_clear_page_bits(struct address_space *, loff_t, size= _t); + bool cond); =20 /** * fscache_acquire_volume - Register a volume as desiring caching services @@ -573,24 +572,6 @@ int fscache_write(struct netfs_cache_resources *cres, return ops->write(cres, start_pos, iter, term_func, term_func_priv); } =20 -/** - * fscache_clear_page_bits - Clear the PG_fscache bits from a set of pages - * @mapping: The netfs inode to use as the source - * @start: The start position in @mapping - * @len: The amount of data to unlock - * @caching: If PG_fscache has been set - * - * Clear the PG_fscache flag from a sequence of pages and wake up anyone w= ho's - * waiting. - */ -static inline void fscache_clear_page_bits(struct address_space *mapping, - loff_t start, size_t len, - bool caching) -{ - if (caching) - __fscache_clear_page_bits(mapping, start, len); -} - /** * fscache_write_to_cache - Save a write to the cache and clear PG_fscache * @cookie: The cookie representing the cache object @@ -600,7 +581,6 @@ static inline void fscache_clear_page_bits(struct addre= ss_space *mapping, * @i_size: The new size of the inode * @term_func: The function to call upon completion * @term_func_priv: The private data for @term_func - * @using_pgpriv2: If we're using PG_private_2 to mark in-progress write * @caching: If we actually want to do the caching * * Helper function for a netfs to write dirty data from an inode into the = cache @@ -612,21 +592,19 @@ static inline void fscache_clear_page_bits(struct add= ress_space *mapping, * marked with PG_fscache. * * If given, @term_func will be called upon completion and supplied with - * @term_func_priv. Note that if @using_pgpriv2 is set, the PG_private_2 = flags - * will have been cleared by this point, so the netfs must retain its own = pin - * on the mapping. + * @term_func_priv. */ static inline void fscache_write_to_cache(struct fscache_cookie *cookie, struct address_space *mapping, loff_t start, size_t len, loff_t i_size, netfs_io_terminated_t term_func, void *term_func_priv, - bool using_pgpriv2, bool caching) + bool caching) { if (caching) __fscache_write_to_cache(cookie, mapping, start, len, i_size, term_func, term_func_priv, - using_pgpriv2, caching); + caching); else if (term_func) term_func(term_func_priv, -ENOBUFS, false); =20 --=20 2.43.0