linux-efi.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Ard Biesheuvel <ardb@kernel.org>
To: linux-efi@vger.kernel.org, Ingo Molnar <mingo@kernel.org>,
	Thomas Gleixner <tglx@linutronix.de>
Cc: Ard Biesheuvel <ardb@kernel.org>,
	linux-kernel@vger.kernel.org,
	Arvind Sankar <nivedita@alum.mit.edu>,
	Christoph Hellwig <hch@lst.de>,
	David Hildenbrand <david@redhat.com>,
	Davidlohr Bueso <dave@stgolabs.net>,
	Guenter Roeck <linux@roeck-us.net>,
	Heinrich Schuchardt <xypron.glpk@gmx.de>,
	Jonathan Corbet <corbet@lwn.net>,
	Lukas Bulwahn <lukas.bulwahn@gmail.com>,
	Masahiro Yamada <masahiroy@kernel.org>,
	Nikolai Merinov <n.merinov@inango-systems.com>,
	Tom Lendacky <thomas.lendacky@amd.com>,
	Vladis Dronov <vdronov@redhat.com>
Subject: [PATCH 14/28] efi/libstub/x86: deal with exit() boot service returning
Date: Sun,  8 Mar 2020 09:08:45 +0100	[thread overview]
Message-ID: <20200308080859.21568-15-ardb@kernel.org> (raw)
In-Reply-To: <20200308080859.21568-1-ardb@kernel.org>

Even though it is uncommon, there are cases where the Exit() EFI boot
service might return, e.g., when we were booted via the EFI handover
protocol from OVMF and the kernel image was specified on the command
line, in which case Exit() attempts to terminate the boot manager,
which is not an EFI application itself. So let's drop into a deadloop
instead.

Tested-by: Nathan Chancellor <natechancellor@gmail.com> # build
Link: https://lore.kernel.org/r/20200303080648.21427-1-ardb@kernel.org
[ardb: put 'hlt' in deadloop]
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
---
 drivers/firmware/efi/libstub/x86-stub.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/firmware/efi/libstub/x86-stub.c b/drivers/firmware/efi/libstub/x86-stub.c
index 7f3e97c2aad3..69a942f0640b 100644
--- a/drivers/firmware/efi/libstub/x86-stub.c
+++ b/drivers/firmware/efi/libstub/x86-stub.c
@@ -344,7 +344,8 @@ static void setup_graphics(struct boot_params *boot_params)
 static void __noreturn efi_exit(efi_handle_t handle, efi_status_t status)
 {
 	efi_bs_call(exit, handle, status, 0, NULL);
-	unreachable();
+	for(;;)
+		asm("hlt");
 }
 
 void startup_32(struct boot_params *boot_params);
-- 
2.17.1


  parent reply	other threads:[~2020-03-08  8:09 UTC|newest]

Thread overview: 30+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-03-08  8:08 [GIT PULL 00/28] More EFI fixes for v5.7 Ard Biesheuvel
2020-03-08  8:08 ` [PATCH 01/28] efi/x86: Add TPM related EFI tables to unencrypted mapping checks Ard Biesheuvel
2020-03-08  8:08 ` [PATCH 02/28] efi/x86: Add RNG seed EFI table to unencrypted mapping check Ard Biesheuvel
2020-03-08  8:08 ` [PATCH 03/28] efi: don't shadow i in efi_config_parse_tables() Ard Biesheuvel
2020-03-08  8:08 ` [PATCH 04/28] efi/arm: clean EFI stub exit code from cache instead of avoiding it Ard Biesheuvel
2020-03-08  8:08 ` [PATCH 05/28] efi/arm64: " Ard Biesheuvel
2020-03-08  8:08 ` [PATCH 06/28] efi: mark all EFI runtime services as unsupported on non-EFI boot Ard Biesheuvel
2020-03-08  8:08 ` [PATCH 07/28] MAINTAINERS: adjust EFI entry to removing eboot.c Ard Biesheuvel
2020-03-08  8:08 ` [PATCH 08/28] efi/libstub: add libstub/mem.c to documentation tree Ard Biesheuvel
2020-03-08  8:08 ` [PATCH 09/28] efi/x86: Annotate the LOADED_IMAGE_PROTOCOL_GUID with SYM_DATA Ard Biesheuvel
2020-03-08  8:08 ` [PATCH 10/28] efi/x86: Respect 32-bit ABI in efi32_pe_entry Ard Biesheuvel
2020-03-08  8:08 ` [PATCH 11/28] efi/x86: Make efi32_pe_entry more readable Ard Biesheuvel
2020-03-08  8:08 ` [PATCH 12/28] efi/x86: Avoid using code32_start Ard Biesheuvel
2020-03-08  8:08 ` [PATCH 13/28] x86/boot: Use unsigned comparison for addresses Ard Biesheuvel
2020-03-08  8:08 ` Ard Biesheuvel [this message]
2020-03-08  8:08 ` [PATCH 15/28] x86/boot/compressed/32: Save the output address instead of recalculating it Ard Biesheuvel
2020-03-08  8:08 ` [PATCH 16/28] efi/x86: Decompress at start of PE image load address Ard Biesheuvel
2020-03-08  8:08 ` [PATCH 17/28] efi/x86: Add kernel preferred address to PE header Ard Biesheuvel
2020-03-08  8:08 ` [PATCH 18/28] efi/x86: Remove extra headroom for setup block Ard Biesheuvel
2020-03-08  8:08 ` [PATCH 19/28] efi/x86: Don't relocate the kernel unless necessary Ard Biesheuvel
2020-03-08  8:08 ` [PATCH 20/28] efi/x86: ignore memory attributes table on i386 Ard Biesheuvel
2020-03-08  8:08 ` [PATCH 21/28] efi/x86: preserve %ebx correctly in efi_set_virtual_address_map() Ard Biesheuvel
2020-03-08  8:08 ` [PATCH 22/28] efi/libstub: avoid linking libstub/lib-ksyms.o into vmlinux Ard Biesheuvel
2020-03-08  8:08 ` [PATCH 23/28] efi: fix a race and a buffer overflow while reading efivars via sysfs Ard Biesheuvel
2020-03-08  8:08 ` [PATCH 24/28] efi: add a sanity check to efivar_store_raw() Ard Biesheuvel
2020-03-08  8:08 ` [PATCH 25/28] efi: fix a mistype in comments mentioning efivar_entry_iter_begin() Ard Biesheuvel
2020-03-08  8:08 ` [PATCH 26/28] efi/libstub/x86: use ULONG_MAX as upper bound for all allocations Ard Biesheuvel
2020-03-08  8:08 ` [PATCH 27/28] efi/x86: Fix cast of image argument Ard Biesheuvel
2020-03-08  8:08 ` [PATCH 28/28] partitions/efi: Fix partition name parsing in GUID partition entry Ard Biesheuvel
2020-03-08  9:00 ` [GIT PULL 00/28] More EFI fixes for v5.7 Ingo Molnar

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=20200308080859.21568-15-ardb@kernel.org \
    --to=ardb@kernel.org \
    --cc=corbet@lwn.net \
    --cc=dave@stgolabs.net \
    --cc=david@redhat.com \
    --cc=hch@lst.de \
    --cc=linux-efi@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux@roeck-us.net \
    --cc=lukas.bulwahn@gmail.com \
    --cc=masahiroy@kernel.org \
    --cc=mingo@kernel.org \
    --cc=n.merinov@inango-systems.com \
    --cc=nivedita@alum.mit.edu \
    --cc=tglx@linutronix.de \
    --cc=thomas.lendacky@amd.com \
    --cc=vdronov@redhat.com \
    --cc=xypron.glpk@gmx.de \
    /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).