lkml.org 
[lkml]   [2023]   [Aug]   [1]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH RESEND v9 13/36] x86/fred: Let ret_from_fork_asm() jmp to fred_exit_user when FRED is enabled
Date
From: "H. Peter Anvin (Intel)" <hpa@zytor.com>

Let ret_from_fork_asm() jmp to fred_exit_user when FRED is enabled,
otherwise the existing IDT code is chosen.

Signed-off-by: H. Peter Anvin (Intel) <hpa@zytor.com>
Tested-by: Shan Kang <shan.kang@intel.com>
Signed-off-by: Xin Li <xin3.li@intel.com>
---
arch/x86/entry/entry_64.S | 6 ++++++
1 file changed, 6 insertions(+)

diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S
index 43606de22511..8069151176f2 100644
--- a/arch/x86/entry/entry_64.S
+++ b/arch/x86/entry/entry_64.S
@@ -309,7 +309,13 @@ SYM_CODE_START(ret_from_fork_asm)
* and unwind should work normally.
*/
UNWIND_HINT_REGS
+
+#ifdef CONFIG_X86_FRED
+ ALTERNATIVE "jmp swapgs_restore_regs_and_return_to_usermode", \
+ "jmp fred_exit_user", X86_FEATURE_FRED
+#else
jmp swapgs_restore_regs_and_return_to_usermode
+#endif
SYM_CODE_END(ret_from_fork_asm)
.popsection

--
2.34.1
\
 
 \ /
  Last update: 2023-08-01 11:05    [W:0.538 / U:0.000 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site