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 5F63D3A9018 for ; Fri, 3 Apr 2026 12:55:24 +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=1775220924; cv=none; b=JfGeSTu97f0OEJhNK9X5DuCPuzoimOJ58Ihl/zN/10bq9AUX8U/KzdNWu6hhAiGIK1zIla/8vP9cmkOC4UZthoF+oowtrER2gnG8fidzEElXxbQlCVfvYpQBHLF2GR/IMnpLESJ3dXhsFVEGaFtV9H3J3/h+XTLope4LgyyDcr8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775220924; c=relaxed/simple; bh=hRHbs1nZiBxTW53Dr0PK/q49gOnA+srDX4sDHcKT/U0=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=O/CJKtIm3VUH053v2xo6qMpWSulZgbIsCM4w7Cu0vmIFhBteOIpevj2JcvHwNsxntUfANJxcguT9uU3pYW/HzmfrAHfT3qOoJX80imVlNPegXySX284RxTs3sytzBWloRiklO+NlSM+mTCuUjFVIInjdcFY/o039CVrfnR8l/gA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=KupXL9c1; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="KupXL9c1" Received: by smtp.kernel.org (Postfix) with ESMTPSA id AF89AC4CEF7; Fri, 3 Apr 2026 12:55:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1775220923; bh=hRHbs1nZiBxTW53Dr0PK/q49gOnA+srDX4sDHcKT/U0=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=KupXL9c1SOTFLELhbeEvZqVLN9rUlFO3MhzaB6z2L09ny7U2mHCyQHaKmI3iSeIup pEJ84bkq93g8ZA0fS249HT5PeBcFO3yixizyo7mcR4uN0ek/QI8BROkzGaqeoC+qoK 012NavwbizjkM/9cZrZm1ekueAfoHaCKyJgdkfErXW6Cd1UOBTP0j6Zr5s34ViQxa1 5y2nC+Hkk0cO3qQnB/QrS5Hr6XvODNu8ZaST2GTW/M7vJKT5lMBRERc5ZIP5nwbMZ4 eDzIZ5lXROUgDzWiXcByC+MeXTdM9SH++Gr6OtIfxDGmo6O/sVD6DU06M82jkwRTmK /rCSRYn8TTe/w== Date: Fri, 3 Apr 2026 13:55:20 +0100 From: Simon Horman To: Aleksandr Loktionov Cc: intel-wired-lan@lists.osuosl.org, anthony.l.nguyen@intel.com, netdev@vger.kernel.org, Sergey Temerkhanov Subject: Re: [PATCH net] ice: use READ_ONCE() to access cached PHC time Message-ID: <20260403125520.GA105440@horms.kernel.org> References: <20260327072332.130320-1-aleksandr.loktionov@intel.com> <20260327072332.130320-9-aleksandr.loktionov@intel.com> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260327072332.130320-9-aleksandr.loktionov@intel.com> On Fri, Mar 27, 2026 at 08:23:32AM +0100, Aleksandr Loktionov wrote: > From: Sergey Temerkhanov > > ptp.cached_phc_time is a 64-bit value updated by a periodic work item > on one CPU and read locklessly on another. On 32-bit or non-atomic > architectures this can result in a torn read. Use READ_ONCE() to > enforce a single atomic load. > > Fixes: 77a781155a65 ("ice: enable receive hardware timestamping") > Cc: stable@vger.kernel.org > Signed-off-by: Sergey Temerkhanov > Signed-off-by: Aleksandr Loktionov Reviewed-by: Simon Horman