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 5/6] x86/entry/32: Remove SEP test for SYSEXIT
Date: Fri, 21 Jul 2023 12:10:16 -0400 [thread overview]
Message-ID: <20230721161018.50214-6-brgerst@gmail.com> (raw)
In-Reply-To: <20230721161018.50214-1-brgerst@gmail.com>
SEP must be already be present in order for do_fast_syscall_32() to be
called on native 32-bit, so checking it again is unnecessary.
Signed-off-by: Brian Gerst <brgerst@gmail.com>
---
arch/x86/entry/common.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)
diff --git a/arch/x86/entry/common.c b/arch/x86/entry/common.c
index 5b3594457af3..4d7d6d25dda9 100644
--- a/arch/x86/entry/common.c
+++ b/arch/x86/entry/common.c
@@ -265,8 +265,7 @@ __visible noinstr bool do_fast_syscall_32(struct pt_regs *regs)
* We don't allow syscalls at all from VM86 mode, but we still
* need to check VM, because we might be returning from sys_vm86.
*/
- return static_cpu_has(X86_FEATURE_SEP) &&
- regs->cs == __USER_CS && regs->ss == __USER_DS &&
+ return regs->cs == __USER_CS && regs->ss == __USER_DS &&
regs->ip == landing_pad &&
(regs->flags & (X86_EFLAGS_RF | X86_EFLAGS_TF | X86_EFLAGS_VM)) == 0;
#endif
--
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 ` [PATCH v2 3/6] x86/entry/compat: Combine return value test from syscall handler Brian Gerst
2023-10-05 8:28 ` [tip: x86/entry] " 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 ` Brian Gerst [this message]
2023-10-05 8:28 ` [tip: x86/entry] x86/entry/32: Remove SEP test for SYSEXIT 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
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