From: Peter Zijlstra <peterz@infradead.org>
To: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: artem.bityutskiy@linux.intel.com,
Patryk Wlazlyn <patryk.wlazlyn@linux.intel.com>,
x86@kernel.org, linux-kernel@vger.kernel.org,
linux-pm@vger.kernel.org, rafael.j.wysocki@intel.com,
len.brown@intel.com, dave.hansen@linux.intel.com
Subject: Re: [PATCH v3 2/3] x86/smp native_play_dead: Prefer cpuidle_play_dead() over mwait_play_dead()
Date: Tue, 12 Nov 2024 16:08:09 +0100 [thread overview]
Message-ID: <20241112150809.GK6497@noisy.programming.kicks-ass.net> (raw)
In-Reply-To: <CAJZ5v0iYYYpg7MDf8_UmoUuzyiPMoPdjgSJmdBXGYCxVc4icWw@mail.gmail.com>
On Tue, Nov 12, 2024 at 03:56:22PM +0100, Rafael J. Wysocki wrote:
> > So given we don't have any such code, why can't we simply fix the cstate
> > parsing we have in mwait_play_dead() and call it a day?
>
> I'll leave this one to Artem, but there is at least one reason to
> avoid doing that I know about: There is no guarantee that whatever has
> been found was actually validated.
It's a bit daft to explicitly advertise a state in CPUID that's not
validated. I realize that MSFT will likely only ever use the ACPI table,
but at the same time, the CPUID bits and ACPI tables both come from the
same BIOS image, no?
.... and we've never seen the BIOS be self contradictory before ... /me
runs
next prev parent reply other threads:[~2024-11-12 15:08 UTC|newest]
Thread overview: 51+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-11-08 12:29 [PATCH v3 0/3] SRF: Fix offline CPU preventing pc6 entry Patryk Wlazlyn
2024-11-08 12:29 ` [PATCH v3 1/3] x86/smp: Allow calling mwait_play_dead with arbitrary hint Patryk Wlazlyn
2024-11-08 16:03 ` Dave Hansen
2024-11-12 10:54 ` Patryk Wlazlyn
2024-11-08 12:29 ` [PATCH v3 2/3] x86/smp native_play_dead: Prefer cpuidle_play_dead() over mwait_play_dead() Patryk Wlazlyn
2024-11-08 16:14 ` Dave Hansen
2024-11-12 10:55 ` Patryk Wlazlyn
2024-11-12 11:47 ` Peter Zijlstra
2024-11-12 12:03 ` Rafael J. Wysocki
2024-11-12 12:18 ` Peter Zijlstra
2024-11-12 12:30 ` Rafael J. Wysocki
2024-11-12 12:38 ` Rafael J. Wysocki
2024-11-12 13:49 ` Peter Zijlstra
2024-11-12 14:56 ` Rafael J. Wysocki
2024-11-12 15:08 ` Peter Zijlstra [this message]
2024-11-12 16:24 ` Rafael J. Wysocki
2024-11-12 12:44 ` Artem Bityutskiy
2024-11-12 14:01 ` Peter Zijlstra
2024-11-14 12:03 ` Peter Zijlstra
2024-11-15 1:21 ` Thomas Gleixner
2024-11-15 10:07 ` Peter Zijlstra
2024-11-15 15:37 ` Thomas Gleixner
2024-11-12 13:23 ` Rafael J. Wysocki
2024-11-12 14:56 ` Peter Zijlstra
2024-11-12 15:00 ` Rafael J. Wysocki
2024-11-13 11:41 ` Gautham R. Shenoy
2024-11-13 16:14 ` Dave Hansen
2024-11-14 5:06 ` Gautham R. Shenoy
2024-11-13 16:22 ` Peter Zijlstra
2024-11-13 16:27 ` Wysocki, Rafael J
2024-11-14 11:58 ` Rafael J. Wysocki
2024-11-14 12:17 ` Peter Zijlstra
2024-11-14 17:36 ` Gautham R. Shenoy
2024-11-14 17:58 ` Rafael J. Wysocki
2024-11-14 11:58 ` Peter Zijlstra
2024-11-14 17:24 ` Gautham R. Shenoy
2024-11-15 10:11 ` Peter Zijlstra
2024-11-25 5:45 ` Gautham R. Shenoy
2024-11-08 12:29 ` [PATCH v3 3/3] intel_idle: Provide enter_dead() handler for SRF Patryk Wlazlyn
2024-11-08 16:21 ` Dave Hansen
2024-11-12 10:57 ` Patryk Wlazlyn
2024-11-12 11:28 ` Rafael J. Wysocki
2024-11-12 16:07 ` Dave Hansen
2024-11-12 19:17 ` Thomas Gleixner
2024-11-12 19:43 ` Rafael J. Wysocki
2024-11-08 22:12 ` kernel test robot
2024-11-08 16:22 ` [PATCH v3 0/3] SRF: Fix offline CPU preventing pc6 entry Dave Hansen
2024-11-12 11:45 ` Peter Zijlstra
2024-11-12 15:43 ` Patryk Wlazlyn
2024-11-13 1:19 ` Thomas Gleixner
2024-11-14 17:13 ` Patryk Wlazlyn
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