linux-kernel - Re: [PATCH v3 02/47] arm_mpam: Use non-atomic bitops when modifying feature bitmap

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <cf2cc08b-9170-4ef2-9f99-e2d901b40c61@redhat.com>
Date: Thu, 15 Jan 2026 10:14:48 +0800
From: Gavin Shan <gshan@...hat.com>
To: Ben Horgan <ben.horgan@....com>
Cc: amitsinght@...vell.com, baisheng.gao@...soc.com,
 baolin.wang@...ux.alibaba.com, carl@...amperecomputing.com,
 dave.martin@....com, david@...nel.org, dfustini@...libre.com,
 fenghuay@...dia.com, james.morse@....com, jonathan.cameron@...wei.com,
 kobak@...dia.com, lcherian@...vell.com,
 linux-arm-kernel@...ts.infradead.org, linux-kernel@...r.kernel.org,
 peternewman@...gle.com, punit.agrawal@....qualcomm.com,
 quic_jiles@...cinc.com, reinette.chatre@...el.com, rohit.mathew@....com,
 scott@...amperecomputing.com, sdonthineni@...dia.com,
 tan.shaopeng@...itsu.com, xhao@...ux.alibaba.com, catalin.marinas@....com,
 will@...nel.org, corbet@....net, maz@...nel.org, oupton@...nel.org,
 joey.gouly@....com, suzuki.poulose@....com, kvmarm@...ts.linux.dev
Subject: Re: [PATCH v3 02/47] arm_mpam: Use non-atomic bitops when modifying
 feature bitmap

On 1/13/26 12:58 AM, Ben Horgan wrote:
> In the test__props_mismatch() kunit test we rely on the struct mpam_props
> being packed to ensure memcmp doesn't consider packing. Making it packed
> reduces the alignment of the features bitmap and so breaks a requirement
> for the use of atomics. As we don't rely on the set/clear of these bits
> being atomic, just make them non-atomic.
> 
> Reviewed-by: Jonathan Cameron <jonathan.cameron@...wei.com>
> Signed-off-by: Ben Horgan <ben.horgan@....com>
> ---
> Changes since v2:
> Add comment (Jonathan)
> ---
>   drivers/resctrl/mpam_internal.h | 8 ++++++--
>   1 file changed, 6 insertions(+), 2 deletions(-)
> 

Reviewed-by: Gavin Shan <gshan@...hat.com>