From: Brian Gerst <brgerst@gmail.com>
To: linux-kernel@vger.kernel.org, x86@kernel.org
Cc: "Thomas Gleixner" <tglx@linutronix.de>,
"Borislav Petkov" <bp@alien8.de>,
"H . Peter Anvin" <hpa@zytor.com>,
"Andy Lutomirski" <luto@kernel.org>,
"Mika Penttilä" <mpenttil@redhat.com>,
"Brian Gerst" <brgerst@gmail.com>
Subject: [PATCH v2 3/6] x86/entry/compat: Combine return value test from syscall handler
Date: Fri, 21 Jul 2023 12:10:14 -0400 [thread overview]
Message-ID: <20230721161018.50214-4-brgerst@gmail.com> (raw)
In-Reply-To: <20230721161018.50214-1-brgerst@gmail.com>
Move the sysret32_from_system_call label to remove a duplicate test of
the return value from the syscall handler.
Signed-off-by: Brian Gerst <brgerst@gmail.com>
---
arch/x86/entry/entry_64_compat.S | 9 ++++-----
1 file changed, 4 insertions(+), 5 deletions(-)
diff --git a/arch/x86/entry/entry_64_compat.S b/arch/x86/entry/entry_64_compat.S
index 70150298f8bd..b16272395f1a 100644
--- a/arch/x86/entry/entry_64_compat.S
+++ b/arch/x86/entry/entry_64_compat.S
@@ -118,9 +118,6 @@ SYM_INNER_LABEL(entry_SYSENTER_compat_after_hwframe, SYM_L_GLOBAL)
movq %rsp, %rdi
call do_SYSENTER_32
- /* XEN PV guests always use IRET path */
- ALTERNATIVE "testl %eax, %eax; jz swapgs_restore_regs_and_return_to_usermode", \
- "jmp swapgs_restore_regs_and_return_to_usermode", X86_FEATURE_XENPV
jmp sysret32_from_system_call
.Lsysenter_fix_flags:
@@ -212,13 +209,15 @@ SYM_INNER_LABEL(entry_SYSCALL_compat_after_hwframe, SYM_L_GLOBAL)
movq %rsp, %rdi
call do_fast_syscall_32
+
+sysret32_from_system_call:
/* XEN PV guests always use IRET path */
ALTERNATIVE "testl %eax, %eax; jz swapgs_restore_regs_and_return_to_usermode", \
"jmp swapgs_restore_regs_and_return_to_usermode", X86_FEATURE_XENPV
- /* Opportunistic SYSRET */
-sysret32_from_system_call:
/*
+ * Opportunistic SYSRET
+ *
* We are not going to return to userspace from the trampoline
* stack. So let's erase the thread stack right now.
*/
--
2.41.0
next prev parent reply other threads:[~2023-07-21 16:11 UTC|newest]
Thread overview: 22+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-07-21 16:10 [PATCH v2 0/6] x86: Clean up fast syscall return validation Brian Gerst
2023-07-21 16:10 ` [PATCH v2 1/6] x86/entry/64: Remove obsolete comment on tracing vs. SYSRET Brian Gerst
2023-10-05 8:28 ` [tip: x86/entry] " tip-bot2 for Brian Gerst
2023-07-21 16:10 ` [PATCH v2 2/6] x86/entry/64: Convert SYSRET validation tests to C Brian Gerst
2023-07-23 9:53 ` Li, Xin3
2023-07-23 11:17 ` Brian Gerst
2023-07-21 16:10 ` Brian Gerst [this message]
2023-10-05 8:28 ` [tip: x86/entry] x86/entry/compat: Combine return value test from syscall handler tip-bot2 for Brian Gerst
2023-07-21 16:10 ` [PATCH v2 4/6] x86/entry/32: Convert do_fast_syscall_32() to bool return type Brian Gerst
2023-10-05 8:28 ` [tip: x86/entry] " tip-bot2 for Brian Gerst
2023-07-21 16:10 ` [PATCH v2 5/6] x86/entry/32: Remove SEP test for SYSEXIT Brian Gerst
2023-10-05 8:28 ` [tip: x86/entry] " tip-bot2 for Brian Gerst
2023-07-21 16:10 ` [PATCH v2 6/6] x86/entry/32: Clean up syscall fast exit tests Brian Gerst
2023-10-05 8:22 ` [PATCH v2 0/6] x86: Clean up fast syscall return validation Ingo Molnar
2023-10-05 15:13 ` Brian Gerst
2023-10-05 20:20 ` Ingo Molnar
2023-10-06 18:59 ` H. Peter Anvin
2023-10-06 21:32 ` Brian Gerst
2023-10-07 9:42 ` Ingo Molnar
2023-10-06 23:58 ` H. Peter Anvin
2023-10-07 9:56 ` Uros Bizjak
2023-10-07 18:07 ` Linus Torvalds
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=20230721161018.50214-4-brgerst@gmail.com \
--to=brgerst@gmail.com \
--cc=bp@alien8.de \
--cc=hpa@zytor.com \
--cc=linux-kernel@vger.kernel.org \
--cc=luto@kernel.org \
--cc=mpenttil@redhat.com \
--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
Powered by JetHome