From: Reinette Chatre <reinette.chatre@intel.com>
To: <tony.luck@intel.com>, <james.morse@arm.com>,
<Dave.Martin@arm.com>, <babu.moger@amd.com>, <bp@alien8.de>,
<tglx@linutronix.de>, <dave.hansen@linux.intel.com>
Cc: <x86@kernel.org>, <hpa@zytor.com>, <ben.horgan@arm.com>,
<fustini@kernel.org>, <fenghuay@nvidia.com>,
<peternewman@google.com>, <linux-kernel@vger.kernel.org>,
<patches@lists.linux.dev>
Subject: Re: [PATCH v3 05/13] x86/resctrl: Protect against bad shift
Date: Wed, 8 Apr 2026 09:37:31 -0700 [thread overview]
Message-ID: <70687d1d-a373-4196-b59b-ef7baf337942@intel.com> (raw)
In-Reply-To: <280c162f8b935d6c755027aa382d55e84ba31116.1775576382.git.reinette.chatre@intel.com>
On 4/7/26 9:02 AM, Reinette Chatre wrote:
> diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
> index 7667cf7c4e94..db787c4dee61 100644
> --- a/arch/x86/kernel/cpu/resctrl/core.c
> +++ b/arch/x86/kernel/cpu/resctrl/core.c
> @@ -246,7 +246,9 @@ static __init bool __rdt_get_mem_config_amd(struct rdt_resource *r)
>
> cpuid_count(0x80000020, subleaf, &eax, &ebx, &ecx, &edx);
> hw_res->num_closid = edx + 1;
> - r->membw.max_bw = 1 << eax;
> + if (WARN_ON(BITS_PER_TYPE(r->membw.max_bw) <= eax))
sashiko [1] reminded me about not using WARN_ON().
I'll switch this to pr_warn().
> + return false;
> + r->membw.max_bw = BIT(eax);
>
Reinette
[1] https://sashiko.dev/#/patchset/cover.1775576382.git.reinette.chatre%40intel.com
next prev parent reply other threads:[~2026-04-08 16:37 UTC|newest]
Thread overview: 19+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-04-07 16:01 [PATCH v3 00/13] x86,fs/resctrl: Improve resctrl quality and consistency Reinette Chatre
2026-04-07 16:01 ` [PATCH v3 01/13] MAINTAINERS: Update resctrl entry Reinette Chatre
2026-04-07 16:01 ` [PATCH v3 02/13] fs/resctrl: Add missing return value descriptions Reinette Chatre
2026-04-07 16:02 ` [PATCH v3 03/13] fs/resctrl: Avoid "may be used uninitialized" warning Reinette Chatre
2026-04-07 18:55 ` Borislav Petkov
2026-04-07 20:50 ` Reinette Chatre
2026-04-07 22:19 ` Borislav Petkov
2026-04-07 22:56 ` Reinette Chatre
2026-04-07 16:02 ` [PATCH v3 04/13] fs/resctrl: Use correct format specifier for printing error pointers Reinette Chatre
2026-04-07 16:02 ` [PATCH v3 05/13] x86/resctrl: Protect against bad shift Reinette Chatre
2026-04-08 16:37 ` Reinette Chatre [this message]
2026-04-07 16:02 ` [PATCH v3 06/13] fs/resctrl: Change pattern used to track number of entries in enum Reinette Chatre
2026-04-07 16:02 ` [PATCH v3 07/13] fs/resctrl: Use accurate type for rdt_resource::rid Reinette Chatre
2026-04-07 16:02 ` [PATCH v3 08/13] fs/resctrl: Pass error reading event through to user space Reinette Chatre
2026-04-07 16:02 ` [PATCH v3 09/13] fs/resctrl: Add last_cmd_status support for writes to max_threshold_occupancy Reinette Chatre
2026-04-07 16:02 ` [PATCH v3 10/13] fs/resctrl: Use accurate and symmetric exit flows Reinette Chatre
2026-04-07 16:02 ` [PATCH v3 11/13] fs/resctrl: Change last_cmd_status custom during input parsing Reinette Chatre
2026-04-07 16:02 ` [PATCH v3 12/13] fs/resctrl: Communicate resource group deleted error via last_cmd_status Reinette Chatre
2026-04-07 16:02 ` [PATCH v3 13/13] fs/resctrl: Inform user space when status buffer overflowed Reinette Chatre
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