From: Lai Jiangshan <jiangshanlai@gmail.com>
To: linux-kernel@vger.kernel.org
Cc: Lai Jiangshan <laijs@linux.alibaba.com>,
Andy Lutomirski <luto@kernel.org>,
Thomas Gleixner <tglx@linutronix.de>,
Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
x86@kernel.org, "H. Peter Anvin" <hpa@zytor.com>
Subject: [PATCH V2 17/41] x86/entry: Make paranoid_exit() callable
Date: Sun, 26 Sep 2021 23:08:14 +0800 [thread overview]
Message-ID: <20210926150838.197719-18-jiangshanlai@gmail.com> (raw)
In-Reply-To: <20210926150838.197719-1-jiangshanlai@gmail.com>
From: Lai Jiangshan <laijs@linux.alibaba.com>
Move the last JMP out of paranoid_exit() and make it callable.
Allow paranoid_exit() to be re-written in C later and also allow
asm_exc_nmi() to call it to avoid duplicated code.
No functional change intended.
Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com>
---
arch/x86/entry/entry_64.S | 18 +++++++++++-------
1 file changed, 11 insertions(+), 7 deletions(-)
diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S
index 169ee14cc2d6..202253c9a4f2 100644
--- a/arch/x86/entry/entry_64.S
+++ b/arch/x86/entry/entry_64.S
@@ -443,7 +443,8 @@ SYM_CODE_START(\asmsym)
call \cfunc
- jmp paranoid_exit
+ call paranoid_exit
+ jmp restore_regs_and_return_to_kernel
/* Switch to the regular task stack and use the noist entry point */
.Lfrom_usermode_switch_stack_\@:
@@ -520,7 +521,8 @@ SYM_CODE_START(\asmsym)
* identical to the stack in the IRET frame or the VC fall-back stack,
* so it is definitely mapped even with PTI enabled.
*/
- jmp paranoid_exit
+ call paranoid_exit
+ jmp restore_regs_and_return_to_kernel
/* Switch to the regular task stack */
.Lfrom_usermode_switch_stack_\@:
@@ -550,7 +552,8 @@ SYM_CODE_START(\asmsym)
movq $-1, ORIG_RAX(%rsp) /* no syscall to restart */
call \cfunc
- jmp paranoid_exit
+ call paranoid_exit
+ jmp restore_regs_and_return_to_kernel
_ASM_NOKPROBE(\asmsym)
SYM_CODE_END(\asmsym)
@@ -937,7 +940,7 @@ SYM_CODE_END(paranoid_entry)
* Y User space GSBASE, must be restored unconditionally
*/
SYM_CODE_START_LOCAL(paranoid_exit)
- UNWIND_HINT_REGS
+ UNWIND_HINT_REGS offset=8
/*
* The order of operations is important. RESTORE_CR3 requires
* kernel GSBASE.
@@ -953,16 +956,17 @@ SYM_CODE_START_LOCAL(paranoid_exit)
/* With FSGSBASE enabled, unconditionally restore GSBASE */
wrgsbase %rbx
- jmp restore_regs_and_return_to_kernel
+ ret
.Lparanoid_exit_checkgs:
/* On non-FSGSBASE systems, conditionally do SWAPGS */
testl %ebx, %ebx
- jnz restore_regs_and_return_to_kernel
+ jnz .Lparanoid_exit_done
/* We are returning to a context with user GSBASE */
swapgs
- jmp restore_regs_and_return_to_kernel
+.Lparanoid_exit_done:
+ ret
SYM_CODE_END(paranoid_exit)
SYM_CODE_START_LOCAL(error_return)
--
2.19.1.6.gb485710b
next prev parent reply other threads:[~2021-09-26 15:10 UTC|newest]
Thread overview: 54+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-09-26 15:07 [PATCH V2 00/41] x86/entry/64: Convert a bunch of ASM entry code into C code Lai Jiangshan
2021-09-26 15:07 ` [PATCH V2 01/41] x86/entry: Fix swapgs fence Lai Jiangshan
2021-09-26 20:43 ` Thomas Gleixner
2021-09-27 1:10 ` Lai Jiangshan
2021-09-27 3:27 ` Lai Jiangshan
2021-09-27 7:50 ` Thomas Gleixner
2021-09-26 15:07 ` [PATCH V2 02/41] x86/traps: Remove stack-protector from traps.c Lai Jiangshan
2021-09-27 10:19 ` Borislav Petkov
2021-09-27 10:49 ` Lai Jiangshan
2021-09-27 11:01 ` Borislav Petkov
2021-09-27 14:38 ` Lai Jiangshan
2021-09-26 15:08 ` [PATCH V2 03/41] compiler_types.h: Add __noinstr_section() for noinstr Lai Jiangshan
2021-09-27 18:09 ` Kees Cook
2021-09-26 15:08 ` [PATCH V2 04/41] x86/entry: Introduce __entry_text for entry code written in C Lai Jiangshan
2021-09-30 11:49 ` Borislav Petkov
2021-09-26 15:08 ` [PATCH V2 05/41] x86/entry: Move PTI_USER_* to arch/x86/include/asm/processor-flags.h Lai Jiangshan
2021-09-26 15:08 ` [PATCH V2 06/41] x86: Mark __native_read_cr3() & native_write_cr3() as __always_inline Lai Jiangshan
2021-09-26 15:08 ` [PATCH V2 07/41] x86/traps: Move the declaration of native_irq_return_iret into proto.h Lai Jiangshan
2021-09-26 15:08 ` [PATCH V2 08/41] x86/entry: Add arch/x86/entry/entry64.c for C entry code Lai Jiangshan
2021-09-26 15:08 ` [PATCH V2 09/41] x86/entry: Expose the address of .Lgs_change to entry64.c Lai Jiangshan
2021-09-26 15:08 ` [PATCH V2 10/41] x86/entry: Add C verion of SWITCH_TO_KERNEL_CR3 as switch_to_kernel_cr3() Lai Jiangshan
2021-09-26 15:08 ` [PATCH V2 11/41] x86/entry: Add C user_entry_swapgs_and_fence() and kernel_entry_fence_no_swapgs() Lai Jiangshan
2021-09-26 15:08 ` [PATCH V2 12/41] x86/traps: Move pt_regs only in fixup_bad_iret() Lai Jiangshan
2021-09-26 15:08 ` [PATCH V2 13/41] x86/entry: Switch the stack after error_entry() returns Lai Jiangshan
2021-09-26 15:08 ` [PATCH V2 14/41] x86/entry: move PUSH_AND_CLEAR_REGS out of error_entry Lai Jiangshan
2021-09-26 15:08 ` [PATCH V2 15/41] objtool: Allow .entry.text function using CLD instruction Lai Jiangshan
2021-09-26 15:08 ` [PATCH V2 16/41] x86/entry: Implement the whole error_entry() as C code Lai Jiangshan
2021-09-28 21:34 ` Brian Gerst
2021-09-29 8:45 ` Peter Zijlstra
2021-09-26 15:08 ` Lai Jiangshan [this message]
2021-09-26 15:08 ` [PATCH V2 18/41] x86/entry: Call paranoid_exit() in asm_exc_nmi() Lai Jiangshan
2021-09-26 15:08 ` [PATCH V2 19/41] x86/entry: move PUSH_AND_CLEAR_REGS out of paranoid_entry Lai Jiangshan
2021-09-26 15:08 ` [PATCH V2 20/41] x86/entry: Add the C version ist_switch_to_kernel_cr3() Lai Jiangshan
2021-09-26 15:08 ` [PATCH V2 21/41] x86/entry: Add the C version ist_restore_cr3() Lai Jiangshan
2021-09-26 15:08 ` [PATCH V2 22/41] x86/entry: Add the C version get_percpu_base() Lai Jiangshan
2021-09-26 15:08 ` [PATCH V2 23/41] x86/entry: Add the C version ist_switch_to_kernel_gsbase() Lai Jiangshan
2021-09-26 15:08 ` [PATCH V2 24/41] x86/entry: Implement the C version ist_paranoid_entry() Lai Jiangshan
2021-09-26 15:08 ` [PATCH V2 25/41] x86/entry: Implement the C version ist_paranoid_exit() Lai Jiangshan
2021-09-26 15:08 ` [PATCH V2 26/41] x86/entry: Add a C macro to define the function body for IST in .entry.text Lai Jiangshan
2021-09-26 15:08 ` [PATCH V2 27/41] x86/mce: Remove stack protector from mce/core.c Lai Jiangshan
2021-09-26 15:08 ` [PATCH V2 28/41] x86/debug, mce: Use C entry code Lai Jiangshan
2021-09-26 15:08 ` [PATCH V2 29/41] x86/idtentry.h: Move the definitions *IDTENTRY_{MCE|DEBUG}* up Lai Jiangshan
2021-09-26 15:08 ` [PATCH V2 30/41] x86/nmi: Use DEFINE_IDTENTRY_NMI for nmi Lai Jiangshan
2021-09-26 15:08 ` [PATCH V2 31/41] x86/nmi: Remove stack protector from nmi.c Lai Jiangshan
2021-09-26 15:08 ` [PATCH V2 32/41] x86/nmi: Use C entry code Lai Jiangshan
2021-09-26 15:08 ` [PATCH V2 33/41] x86/entry: Add a C macro to define the function body for IST in .entry.text with an error code Lai Jiangshan
2021-09-26 15:08 ` [PATCH V2 34/41] x86/doublefault: Use C entry code Lai Jiangshan
2021-09-26 15:08 ` [PATCH V2 35/41] x86/sev: Add and use ist_vc_switch_off_ist() Lai Jiangshan
2021-09-26 15:08 ` [PATCH V2 36/41] x86/sev: Remove stack protector from sev.c Lai Jiangshan
2021-09-26 15:08 ` [PATCH V2 37/41] x86/sev: Use C entry code Lai Jiangshan
2021-09-26 15:08 ` [PATCH V2 38/41] x86/entry: Remove ASM function paranoid_entry() and paranoid_exit() Lai Jiangshan
2021-09-26 15:08 ` [PATCH V2 39/41] x86/entry: Remove the unused ASM macros Lai Jiangshan
2021-09-26 15:08 ` [PATCH V2 40/41] x86/entry: Remove save_ret from PUSH_AND_CLEAR_REGS Lai Jiangshan
2021-09-26 15:08 ` [PATCH V2 41/41] x86/syscall/64: Move the checking for sysret to C code Lai Jiangshan
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