From: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
To: 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
Cc: "Rafael J. Wysocki" <rafael@kernel.org>,
Peter Zijlstra <peterz@infradead.org>,
Adrian Hunter <adrian.hunter@intel.com>,
Kuppuswamy Sathyanarayanan
<sathyanarayanan.kuppuswamy@linux.intel.com>,
Elena Reshetova <elena.reshetova@intel.com>,
Jun Nakajima <jun.nakajima@intel.com>,
Rick Edgecombe <rick.p.edgecombe@intel.com>,
Tom Lendacky <thomas.lendacky@amd.com>,
"Kalra, Ashish" <ashish.kalra@amd.com>,
Sean Christopherson <seanjc@google.com>,
"Huang, Kai" <kai.huang@intel.com>, Baoquan He <bhe@redhat.com>,
kexec@lists.infradead.org, linux-coco@lists.linux.dev,
linux-kernel@vger.kernel.org,
"Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Subject: [PATCHv2 05/13] x86/kexec: Keep CR4.MCE set during kexec for TDX guest
Date: Fri, 20 Oct 2023 18:12:34 +0300 [thread overview]
Message-ID: <20231020151242.1814-6-kirill.shutemov@linux.intel.com> (raw)
In-Reply-To: <20231020151242.1814-1-kirill.shutemov@linux.intel.com>
TDX guests are not allowed to clear CR4.MCE. Attempt to clear it leads
to #VE.
Use alternatives to keep the flag during kexec for TDX guests.
The change doesn't affect non-TDX-guest environments.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reviewed-by: Kai Huang <kai.huang@intel.com>
---
arch/x86/kernel/relocate_kernel_64.S | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/arch/x86/kernel/relocate_kernel_64.S b/arch/x86/kernel/relocate_kernel_64.S
index 56cab1bb25f5..bea89814b48e 100644
--- a/arch/x86/kernel/relocate_kernel_64.S
+++ b/arch/x86/kernel/relocate_kernel_64.S
@@ -145,11 +145,16 @@ SYM_CODE_START_LOCAL_NOALIGN(identity_mapped)
* Set cr4 to a known state:
* - physical address extension enabled
* - 5-level paging, if it was enabled before
+ * - Machine check exception on TDX guest. Clearing MCE is not allowed
+ * in TDX guests.
*/
movl $X86_CR4_PAE, %eax
testq $X86_CR4_LA57, %r13
jz 1f
orl $X86_CR4_LA57, %eax
+1:
+ ALTERNATIVE "jmp 1f", "", X86_FEATURE_TDX_GUEST
+ orl $X86_CR4_MCE, %eax
1:
movq %rax, %cr4
--
2.41.0
next prev parent reply other threads:[~2023-10-20 15:13 UTC|newest]
Thread overview: 36+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-10-20 15:12 [PATCHv2 00/13] x86/tdx: Add kexec support Kirill A. Shutemov
2023-10-20 15:12 ` [PATCHv2 01/13] x86/acpi: Extract ACPI MADT wakeup code into a separate file Kirill A. Shutemov
2023-10-20 17:12 ` Kuppuswamy Sathyanarayanan
2023-10-20 15:12 ` [PATCHv2 02/13] kernel/cpu: Add support for declaring CPU offlining not supported Kirill A. Shutemov
2023-10-23 9:30 ` Huang, Kai
2023-10-23 15:31 ` kirill.shutemov
2023-10-23 22:07 ` Huang, Kai
2023-10-28 14:07 ` Thomas Gleixner
2023-10-28 14:12 ` Thomas Gleixner
2023-10-29 14:23 ` Kirill A. Shutemov
2023-10-20 15:12 ` [PATCHv2 03/13] cpu/hotplug, x86/acpi: Disable CPU offlining for ACPI MADT wakeup Kirill A. Shutemov
2023-10-20 15:12 ` [PATCHv2 04/13] x86/kvm: Do not try to disable kvmclock if it was not enabled Kirill A. Shutemov
2023-10-20 15:32 ` Sean Christopherson
2023-10-20 15:41 ` Vitaly Kuznetsov
2023-10-20 17:07 ` Sean Christopherson
2023-10-23 8:45 ` Vitaly Kuznetsov
2023-10-23 14:40 ` Sean Christopherson
2023-10-20 15:12 ` Kirill A. Shutemov [this message]
2023-10-20 15:12 ` [PATCHv2 06/13] x86/mm: Make x86_platform.guest.enc_status_change_*() return errno Kirill A. Shutemov
2023-10-20 15:12 ` [PATCHv2 07/13] x86/mm: Return correct level from lookup_address() if pte is none Kirill A. Shutemov
2023-10-20 15:12 ` [PATCHv2 08/13] x86/tdx: Account shared memory Kirill A. Shutemov
2023-10-20 15:12 ` [PATCHv2 09/13] x86/tdx: Convert shared memory back to private on kexec Kirill A. Shutemov
2023-10-20 15:12 ` [PATCHv2 10/13] x86/mm: Make e820_end_ram_pfn() cover E820_TYPE_ACPI ranges Kirill A. Shutemov
2023-10-20 15:12 ` [PATCHv2 11/13] x86/acpi: Do not attempt to bring up secondary CPUs in kexec case Kirill A. Shutemov
2023-10-24 10:14 ` Huang, Kai
2023-10-24 13:59 ` Kuppuswamy Sathyanarayanan
2023-10-27 13:01 ` Kirill A. Shutemov
2023-10-20 15:12 ` [PATCHv2 12/13] x86/acpi: Rename fields in acpi_madt_multiproc_wakeup structure Kirill A. Shutemov
2023-10-24 10:18 ` Huang, Kai
2023-10-24 12:46 ` Kuppuswamy Sathyanarayanan
2023-10-20 15:12 ` [PATCHv2 13/13] x86/acpi: Add support for CPU offlining for ACPI MADT wakeup method Kirill A. Shutemov
2023-10-24 10:11 ` Huang, Kai
2023-10-25 3:50 ` Huang, Kai
2023-10-27 11:58 ` kirill.shutemov
2023-10-29 17:31 ` Thomas Gleixner
2023-11-01 13:26 ` Kirill A. Shutemov
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=20231020151242.1814-6-kirill.shutemov@linux.intel.com \
--to=kirill.shutemov@linux.intel.com \
--cc=adrian.hunter@intel.com \
--cc=ashish.kalra@amd.com \
--cc=bhe@redhat.com \
--cc=bp@alien8.de \
--cc=dave.hansen@linux.intel.com \
--cc=elena.reshetova@intel.com \
--cc=jun.nakajima@intel.com \
--cc=kai.huang@intel.com \
--cc=kexec@lists.infradead.org \
--cc=linux-coco@lists.linux.dev \
--cc=linux-kernel@vger.kernel.org \
--cc=mingo@redhat.com \
--cc=peterz@infradead.org \
--cc=rafael@kernel.org \
--cc=rick.p.edgecombe@intel.com \
--cc=sathyanarayanan.kuppuswamy@linux.intel.com \
--cc=seanjc@google.com \
--cc=tglx@linutronix.de \
--cc=thomas.lendacky@amd.com \
--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 NNTP newsgroup(s).