From: Josh Poimboeuf <jpoimboe@kernel.org>
To: Sean Christopherson <seanjc@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>,
Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
Dave Hansen <dave.hansen@linux.intel.com>,
x86@kernel.org, Peter Zijlstra <peterz@infradead.org>,
linux-kernel@vger.kernel.org,
Stephen Rothwell <sfr@canb.auug.org.au>,
Michael Ellerman <mpe@ellerman.id.au>,
Geert Uytterhoeven <geert@linux-m68k.org>,
Will Deacon <will@kernel.org>,
Linus Torvalds <torvalds@linux-foundation.org>
Subject: Re: [PATCH v2 1/2] cpu: Re-enable CPU mitigations by default for !X86 architectures
Date: Tue, 23 Apr 2024 22:38:06 -0700 [thread overview]
Message-ID: <20240424053806.5u5klchl3pvqu2zw@treble> (raw)
In-Reply-To: <20240420000556.2645001-2-seanjc@google.com>
On Fri, Apr 19, 2024 at 05:05:54PM -0700, Sean Christopherson wrote:
> Rename x86's to CPU_MITIGATIONS, define it in generic code, and force it
> on for all architectures exception x86. A recent commit to turn
> mitigations off by default if SPECULATION_MITIGATIONS=n kinda sorta missed
> that "cpu_mitigations" is completely generic, whereas
> SPECULATION_MITIGATIONS is x86 specific.
>
> Rename x86's SPECULATIVE_MITIGATIONS instead of keeping both and have it
> select CPU_MITIGATIONS, as having two configs for the same thing is
> unnecessary and confusing. This will also allow x86 to use the knob to
> manage mitigations that aren't strictly related to speculative execution.
>
> Use another Kconfig to communicate to common code that CPU_MITIGATIONS is
> already defined instead of having x86's menu depend on the common
> CPU_MITIGATIONS. This allows keeping a single point of contact for all of
> x86's mitigations, and it's not clear that other architectures *want* to
> allow disabling mitigations at compile-time.
>
> Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
> Reported-by: Michael Ellerman <mpe@ellerman.id.au>
> Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
> Closes: https://lkml.kernel.org/r/20240413115324.53303a68%40canb.auug.org.au
> Fixes: f337a6a21e2f ("x86/cpu: Actually turn off mitigations by default for SPECULATION_MITIGATIONS=n")
> Cc: Josh Poimboeuf <jpoimboe@kernel.org>
> Cc: Will Deacon <will@kernel.org>
> Cc: Linus Torvalds <torvalds@linux-foundation.org>
> Cc: stable@vger.kernel.org
> Signed-off-by: Sean Christopherson <seanjc@google.com>
Acked-by: Josh Poimboeuf <jpoimboe@kernel.org>
--
Josh
next prev parent reply other threads:[~2024-04-24 5:38 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-04-20 0:05 [PATCH v2 0/2] cpu: Fix default mitigation behavior Sean Christopherson
2024-04-20 0:05 ` [PATCH v2 1/2] cpu: Re-enable CPU mitigations by default for !X86 architectures Sean Christopherson
2024-04-24 5:38 ` Josh Poimboeuf [this message]
2024-04-25 14:18 ` [tip: x86/urgent] " tip-bot2 for Sean Christopherson
2024-04-20 0:05 ` [PATCH v2 2/2] cpu: Ignore "mitigations" kernel parameter if CPU_MITIGATIONS=n Sean Christopherson
2024-04-20 13:36 ` Borislav Petkov
2024-04-24 5:39 ` Josh Poimboeuf
2024-04-24 13:42 ` Borislav Petkov
2024-04-24 15:48 ` Sean Christopherson
2024-04-25 14:18 ` [tip: x86/urgent] " tip-bot2 for Sean Christopherson
2024-04-20 13:33 ` [PATCH v2 0/2] cpu: Fix default mitigation behavior Borislav Petkov
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20240424053806.5u5klchl3pvqu2zw@treble \
--to=jpoimboe@kernel.org \
--cc=bp@alien8.de \
--cc=dave.hansen@linux.intel.com \
--cc=geert@linux-m68k.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mingo@redhat.com \
--cc=mpe@ellerman.id.au \
--cc=peterz@infradead.org \
--cc=seanjc@google.com \
--cc=sfr@canb.auug.org.au \
--cc=tglx@linutronix.de \
--cc=torvalds@linux-foundation.org \
--cc=will@kernel.org \
--cc=x86@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.