From: Tom Lendacky <thomas.lendacky@amd.com>
To: Ravi Bangoria <ravi.bangoria@amd.com>,
tglx@linutronix.de, mingo@redhat.com, bp@alien8.de,
dave.hansen@linux.intel.com, seanjc@google.com,
pbonzini@redhat.com
Cc: hpa@zytor.com, rmk+kernel@armlinux.org.uk, peterz@infradead.org,
james.morse@arm.com, lukas.bulwahn@gmail.com,
arjan@linux.intel.com, j.granados@samsung.com,
sibs@chinatelecom.cn, nik.borisov@suse.com, michael.roth@amd.com,
nikunj.dadhania@amd.com, babu.moger@amd.com, x86@kernel.org,
kvm@vger.kernel.org, linux-kernel@vger.kernel.org,
santosh.shukla@amd.com, ananth.narayan@amd.com,
sandipan.das@amd.com
Subject: Re: [PATCH 2/3] x86/bus_lock: Add support for AMD
Date: Mon, 6 May 2024 11:05:17 -0500 [thread overview]
Message-ID: <bb6a554f-4823-59ce-16a4-48bd5b911d63@amd.com> (raw)
In-Reply-To: <20240429060643.211-3-ravi.bangoria@amd.com>
On 4/29/24 01:06, Ravi Bangoria wrote:
> Upcoming AMD uarch will support Bus Lock Detect (called Bus Lock Trap
> in AMD docs). Add support for the same in Linux. Bus Lock Detect is
> enumerated with cpuid CPUID Fn0000_0007_ECX_x0 bit [24 / BUSLOCKTRAP].
> It can be enabled through MSR_IA32_DEBUGCTLMSR. When enabled, hardware
> clears DR6[11] and raises a #DB exception on occurrence of Bus Lock if
> CPL > 0. More detail about the feature can be found in AMD APM[1].
>
> [1]: AMD64 Architecture Programmer's Manual Pub. 40332, Rev. 4.07 - June
> 2023, Vol 2, 13.1.3.6 Bus Lock Trap
> https://bugzilla.kernel.org/attachment.cgi?id=304653
>
> Signed-off-by: Ravi Bangoria <ravi.bangoria@amd.com>
> ---
> arch/x86/kernel/cpu/amd.c | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c
> index 39f316d50ae4..013d16479a24 100644
> --- a/arch/x86/kernel/cpu/amd.c
> +++ b/arch/x86/kernel/cpu/amd.c
> @@ -1058,6 +1058,8 @@ static void init_amd(struct cpuinfo_x86 *c)
>
> /* AMD CPUs don't need fencing after x2APIC/TSC_DEADLINE MSR writes. */
> clear_cpu_cap(c, X86_FEATURE_APIC_MSRS_FENCE);
> +
> + bus_lock_init();
Can this call and the one in the intel.c be moved to common.c?
Thanks,
Tom
> }
>
> #ifdef CONFIG_X86_32
next prev parent reply other threads:[~2024-05-06 16:05 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-04-29 6:06 [PATCH 0/3] x86/cpu: Add Bus Lock Detect support for AMD Ravi Bangoria
2024-04-29 6:06 ` [PATCH 1/3] x86/split_lock: Move Split and Bus lock code to a dedicated file Ravi Bangoria
2024-05-06 12:58 ` Borislav Petkov
2024-05-07 4:07 ` Ravi Bangoria
2024-04-29 6:06 ` [PATCH 2/3] x86/bus_lock: Add support for AMD Ravi Bangoria
2024-05-06 16:05 ` Tom Lendacky [this message]
2024-05-07 4:08 ` Ravi Bangoria
2024-05-06 16:24 ` Jim Mattson
2024-05-07 3:57 ` Ravi Bangoria
2024-04-29 6:06 ` [PATCH 3/3] KVM SVM: Add Bus Lock Detect support Ravi Bangoria
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=bb6a554f-4823-59ce-16a4-48bd5b911d63@amd.com \
--to=thomas.lendacky@amd.com \
--cc=ananth.narayan@amd.com \
--cc=arjan@linux.intel.com \
--cc=babu.moger@amd.com \
--cc=bp@alien8.de \
--cc=dave.hansen@linux.intel.com \
--cc=hpa@zytor.com \
--cc=j.granados@samsung.com \
--cc=james.morse@arm.com \
--cc=kvm@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=lukas.bulwahn@gmail.com \
--cc=michael.roth@amd.com \
--cc=mingo@redhat.com \
--cc=nik.borisov@suse.com \
--cc=nikunj.dadhania@amd.com \
--cc=pbonzini@redhat.com \
--cc=peterz@infradead.org \
--cc=ravi.bangoria@amd.com \
--cc=rmk+kernel@armlinux.org.uk \
--cc=sandipan.das@amd.com \
--cc=santosh.shukla@amd.com \
--cc=seanjc@google.com \
--cc=sibs@chinatelecom.cn \
--cc=tglx@linutronix.de \
--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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).