public inbox for stable@vger.kernel.org
 help / color / mirror / Atom feed
From: Nicolas Saenz Julienne <nsaenz@amazon.com>
To: Ard Biesheuvel <ardb@kernel.org>
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>,
	"H . Peter Anvin" <hpa@zytor.com>,
	Matt Fleming <matt@codeblueprint.co.uk>,
	<linux-efi@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
	<stanspas@amazon.de>, <nh-open-source@amazon.com>,
	Nicolas Saenz Julienne <nsaenz@amazon.com>,
	<stable@vger.kernel.org>
Subject: [PATCH v2 2/2] x86/efi: Apply EFI Memory Attributes after kexec
Date: Tue, 12 Nov 2024 18:52:17 +0000	[thread overview]
Message-ID: <20241112185217.48792-2-nsaenz@amazon.com> (raw)
In-Reply-To: <20241112185217.48792-1-nsaenz@amazon.com>

Kexec bypasses EFI's switch to virtual mode. In exchange, it has its own
routine, kexec_enter_virtual_mode(), which replays the mappings made by
the original kernel. Unfortunately, that function fails to reinstate
EFI's memory attributes, which would've otherwise been set after
entering virtual mode. Remediate this by calling
efi_runtime_update_mappings() within kexec's routine.

Cc: stable@vger.kernel.org
Fixes: 18141e89a76c ("x86/efi: Add support for EFI_MEMORY_ATTRIBUTES_TABLE")
Signed-off-by: Nicolas Saenz Julienne <nsaenz@amazon.com>

---

Notes:
- Tested with QEMU/OVMF.

 arch/x86/platform/efi/efi.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c
index 375ebd78296a..a7ff189421c3 100644
--- a/arch/x86/platform/efi/efi.c
+++ b/arch/x86/platform/efi/efi.c
@@ -765,6 +765,7 @@ static void __init kexec_enter_virtual_mode(void)
 
 	efi_sync_low_kernel_mappings();
 	efi_native_runtime_setup();
+	efi_runtime_update_mappings();
 #endif
 }
 
-- 
2.40.1


       reply	other threads:[~2024-11-12 18:52 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <20241112185217.48792-1-nsaenz@amazon.com>
2024-11-12 18:52 ` Nicolas Saenz Julienne [this message]
2024-11-15 16:39   ` [PATCH v2 2/2] x86/efi: Apply EFI Memory Attributes after kexec Ard Biesheuvel
2024-11-18 10:52     ` Nicolas Saenz Julienne
2024-11-22 13:03   ` Dave Young
2024-11-28 15:58     ` Nicolas Saenz Julienne
2024-11-29  7:11       ` Dave Young
2024-11-29  7:31         ` Dave Young
2024-11-29 17:03           ` Nicolas Saenz Julienne

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=20241112185217.48792-2-nsaenz@amazon.com \
    --to=nsaenz@amazon.com \
    --cc=ardb@kernel.org \
    --cc=bp@alien8.de \
    --cc=dave.hansen@linux.intel.com \
    --cc=hpa@zytor.com \
    --cc=linux-efi@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=matt@codeblueprint.co.uk \
    --cc=mingo@redhat.com \
    --cc=nh-open-source@amazon.com \
    --cc=stable@vger.kernel.org \
    --cc=stanspas@amazon.de \
    --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