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Subject[PATCH v2 26/36] x86/entry/32: Switch INT80 to the new C syscall path
Date
Signed-off-by: Andy Lutomirski <luto@kernel.org>
---
arch/x86/entry/entry_32.S | 34 +++++++++++++---------------------
1 file changed, 13 insertions(+), 21 deletions(-)

diff --git a/arch/x86/entry/entry_32.S b/arch/x86/entry/entry_32.S
index 36b6beb181f6..02881e528945 100644
--- a/arch/x86/entry/entry_32.S
+++ b/arch/x86/entry/entry_32.S
@@ -153,13 +153,13 @@

#endif /* CONFIG_X86_32_LAZY_GS */

-.macro SAVE_ALL
+.macro SAVE_ALL pt_regs_ax=%eax
cld
PUSH_GS
pushl %fs
pushl %es
pushl %ds
- pushl %eax
+ pushl \pt_regs_ax
pushl %ebp
pushl %edi
pushl %esi
@@ -370,20 +370,17 @@ ENDPROC(entry_SYSENTER_32)
# system call handler stub
ENTRY(entry_INT80_32)
ASM_CLAC
- pushl %eax # save orig_eax
- SAVE_ALL
- GET_THREAD_INFO(%ebp)
- # system call tracing in operation / emulation
- testl $_TIF_WORK_SYSCALL_ENTRY, TI_flags(%ebp)
- jnz syscall_trace_entry
- cmpl $(NR_syscalls), %eax
- jae syscall_badsys
-syscall_call:
- call *sys_call_table(, %eax, 4)
-syscall_after_call:
- movl %eax, PT_EAX(%esp) # store the return value
-syscall_exit:
- jmp syscall_exit_work
+ pushl %eax /* pt_regs->orig_ax */
+ SAVE_ALL pt_regs_ax=$-ENOSYS /* save rest, load -ENOSYS into ax */
+
+ /*
+ * User mode is traced as though IRQs are on, and the interrupt gate
+ * turned them off.
+ */
+ TRACE_IRQS_OFF
+
+ movl %esp, %eax
+ call do_int80_syscall_32

restore_all:
TRACE_IRQS_IRET
@@ -491,11 +488,6 @@ syscall_fault:
jmp resume_userspace
END(syscall_fault)

-syscall_badsys:
- movl $-ENOSYS, %eax
- jmp syscall_after_call
-END(syscall_badsys)
-
sysenter_badsys:
movl $-ENOSYS, %eax
jmp sysenter_after_call
--
2.4.3


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