From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D9463146A66; Tue, 17 Mar 2026 17:16:40 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773767800; cv=none; b=m9k+kUlgRJvVWFr8TGhneGAEQbMmDO39yZo7kCGj5x1y1lrfBYJCVCoe70eUYUqaAqGHNHDgXOihPj3Sy5g0VZeqA8ftPz2ut6Zj67hBJXOjb6dVKocUQ2xdooKa3r3KriLTcFRjppkgh6DbZWJHJE4BixF8sS1O/d040d8tXsI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773767800; c=relaxed/simple; bh=hk2y3F7wOJtUhPdQ1bJLurR1PQtNC3Ba8N8oEmIy66g=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=XQVnhna2cJRkc08eOh2lcLRoNlWT87g3Q0PmtWSG+j0RGYCXCsuKkvX0XVGkhNtvcEE6M3eKBeHCAVN+mgc0mEITbFBfmfbNc5q2l+KIXu8f10PbIdXBSCSJDHtXDDDVX3iJ1+psiZmP2I/WU9U3BViUU/fhn0AoFjf9KOKcxxg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=HcK9ReHz; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="HcK9ReHz" Received: by smtp.kernel.org (Postfix) with ESMTPSA id DC215C4CEF7; Tue, 17 Mar 2026 17:16:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1773767800; bh=hk2y3F7wOJtUhPdQ1bJLurR1PQtNC3Ba8N8oEmIy66g=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=HcK9ReHz3Q9A0k3v77dcZ/3IN81xai0JysssIxW8KtdDUktB3uBYa5m1leE6MMjTU knxL7uhjv70a+VnQ2Vy0sGlyklWuNGl0tqYDVbCeSpAQajlf4q0H5AEwsH0hebHwWB lJ/V6mtnwR69sMkLMJ5jBXYm6uQHIs62bnZn4cgA= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Adrian Hunter , Penghe Geng , Ulf Hansson Subject: [PATCH 6.18 160/333] mmc: core: Avoid bitfield RMW for claim/retune flags Date: Tue, 17 Mar 2026 17:33:09 +0100 Message-ID: <20260317163005.294835159@linuxfoundation.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260317162959.345812316@linuxfoundation.org> References: <20260317162959.345812316@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Penghe Geng commit 901084c51a0a8fb42a3f37d2e9c62083c495f824 upstream. Move claimed and retune control flags out of the bitfield word to avoid unrelated RMW side effects in asynchronous contexts. The host->claimed bit shared a word with retune flags. Writes to claimed in __mmc_claim_host() or retune_now in mmc_mq_queue_rq() can overwrite other bits when concurrent updates happen in other contexts, triggering spurious WARN_ON(!host->claimed). Convert claimed, can_retune, retune_now and retune_paused to bool to remove shared-word coupling. Fixes: 6c0cedd1ef952 ("mmc: core: Introduce host claiming by context") Fixes: 1e8e55b67030c ("mmc: block: Add CQE support") Cc: stable@vger.kernel.org Suggested-by: Adrian Hunter Signed-off-by: Penghe Geng Acked-by: Adrian Hunter Signed-off-by: Ulf Hansson Signed-off-by: Greg Kroah-Hartman --- include/linux/mmc/host.h | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) --- a/include/linux/mmc/host.h +++ b/include/linux/mmc/host.h @@ -486,14 +486,12 @@ struct mmc_host { struct mmc_ios ios; /* current io bus settings */ + bool claimed; /* host exclusively claimed */ + /* group bitfields together to minimize padding */ unsigned int use_spi_crc:1; - unsigned int claimed:1; /* host exclusively claimed */ unsigned int doing_init_tune:1; /* initial tuning in progress */ - unsigned int can_retune:1; /* re-tuning can be used */ unsigned int doing_retune:1; /* re-tuning in progress */ - unsigned int retune_now:1; /* do re-tuning at next req */ - unsigned int retune_paused:1; /* re-tuning is temporarily disabled */ unsigned int retune_crc_disable:1; /* don't trigger retune upon crc */ unsigned int can_dma_map_merge:1; /* merging can be used */ unsigned int vqmmc_enabled:1; /* vqmmc regulator is enabled */ @@ -508,6 +506,9 @@ struct mmc_host { int rescan_disable; /* disable card detection */ int rescan_entered; /* used with nonremovable devices */ + bool can_retune; /* re-tuning can be used */ + bool retune_now; /* do re-tuning at next req */ + bool retune_paused; /* re-tuning is temporarily disabled */ int need_retune; /* re-tuning is needed */ int hold_retune; /* hold off re-tuning */ unsigned int retune_period; /* re-tuning period in secs */