summaryrefslogtreecommitdiffstats
path: root/arch/x86
diff options
context:
space:
mode:
authorDominik Brodowski <linux@dominikbrodowski.net>2018-02-11 11:49:42 +0100
committerIngo Molnar <mingo@kernel.org>2018-02-13 09:04:52 +0100
commit2e3f0098bc45f710a2f4cbcc94b80a1fae7a99a1 (patch)
tree869d6d7b5b7a6a415980d5910c098e4d1bee1162 /arch/x86
parent21e433bdb95bdf3aa48226fd3d33af608437f293 (diff)
downloadlinux-2e3f0098bc45f710a2f4cbcc94b80a1fae7a99a1.tar.bz2
x86/entry/64: Merge SAVE_C_REGS and SAVE_EXTRA_REGS, remove unused extensions
All current code paths call SAVE_C_REGS and then immediately SAVE_EXTRA_REGS. Therefore, merge these two macros and order the MOV sequeneces properly. While at it, remove the macros to save all except specific registers, as these macros have been unused for a long time. Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: dan.j.williams@intel.com Link: http://lkml.kernel.org/r/20180211104949.12992-2-linux@dominikbrodowski.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/x86')
-rw-r--r--arch/x86/entry/calling.h57
-rw-r--r--arch/x86/entry/entry_64.S12
2 files changed, 19 insertions, 50 deletions
diff --git a/arch/x86/entry/calling.h b/arch/x86/entry/calling.h
index f4b129d4af42..8907a6593b42 100644
--- a/arch/x86/entry/calling.h
+++ b/arch/x86/entry/calling.h
@@ -101,49 +101,22 @@ For 32-bit we have the following conventions - kernel is built with
addq $-(15*8), %rsp
.endm
- .macro SAVE_C_REGS_HELPER offset=0 rax=1 rcx=1 r8910=1 r11=1
- .if \r11
- movq %r11, 6*8+\offset(%rsp)
- .endif
- .if \r8910
- movq %r10, 7*8+\offset(%rsp)
- movq %r9, 8*8+\offset(%rsp)
- movq %r8, 9*8+\offset(%rsp)
- .endif
- .if \rax
- movq %rax, 10*8+\offset(%rsp)
- .endif
- .if \rcx
- movq %rcx, 11*8+\offset(%rsp)
- .endif
- movq %rdx, 12*8+\offset(%rsp)
- movq %rsi, 13*8+\offset(%rsp)
+ .macro SAVE_REGS offset=0
movq %rdi, 14*8+\offset(%rsp)
- UNWIND_HINT_REGS offset=\offset extra=0
- .endm
- .macro SAVE_C_REGS offset=0
- SAVE_C_REGS_HELPER \offset, 1, 1, 1, 1
- .endm
- .macro SAVE_C_REGS_EXCEPT_RAX_RCX offset=0
- SAVE_C_REGS_HELPER \offset, 0, 0, 1, 1
- .endm
- .macro SAVE_C_REGS_EXCEPT_R891011
- SAVE_C_REGS_HELPER 0, 1, 1, 0, 0
- .endm
- .macro SAVE_C_REGS_EXCEPT_RCX_R891011
- SAVE_C_REGS_HELPER 0, 1, 0, 0, 0
- .endm
- .macro SAVE_C_REGS_EXCEPT_RAX_RCX_R11
- SAVE_C_REGS_HELPER 0, 0, 0, 1, 0
- .endm
-
- .macro SAVE_EXTRA_REGS offset=0
- movq %r15, 0*8+\offset(%rsp)
- movq %r14, 1*8+\offset(%rsp)
- movq %r13, 2*8+\offset(%rsp)
- movq %r12, 3*8+\offset(%rsp)
- movq %rbp, 4*8+\offset(%rsp)
+ movq %rsi, 13*8+\offset(%rsp)
+ movq %rdx, 12*8+\offset(%rsp)
+ movq %rcx, 11*8+\offset(%rsp)
+ movq %rax, 10*8+\offset(%rsp)
+ movq %r8, 9*8+\offset(%rsp)
+ movq %r9, 8*8+\offset(%rsp)
+ movq %r10, 7*8+\offset(%rsp)
+ movq %r11, 6*8+\offset(%rsp)
movq %rbx, 5*8+\offset(%rsp)
+ movq %rbp, 4*8+\offset(%rsp)
+ movq %r12, 3*8+\offset(%rsp)
+ movq %r13, 2*8+\offset(%rsp)
+ movq %r14, 1*8+\offset(%rsp)
+ movq %r15, 0*8+\offset(%rsp)
UNWIND_HINT_REGS offset=\offset
.endm
@@ -197,7 +170,7 @@ For 32-bit we have the following conventions - kernel is built with
* is just setting the LSB, which makes it an invalid stack address and is also
* a signal to the unwinder that it's a pt_regs pointer in disguise.
*
- * NOTE: This macro must be used *after* SAVE_EXTRA_REGS because it corrupts
+ * NOTE: This macro must be used *after* SAVE_REGS because it corrupts
* the original rbp.
*/
.macro ENCODE_FRAME_POINTER ptregs_offset=0
diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S
index 932a445febee..1a6fc0136225 100644
--- a/arch/x86/entry/entry_64.S
+++ b/arch/x86/entry/entry_64.S
@@ -573,8 +573,7 @@ END(irq_entries_start)
1:
ALLOC_PT_GPREGS_ON_STACK
- SAVE_C_REGS
- SAVE_EXTRA_REGS
+ SAVE_REGS
CLEAR_REGS_NOSPEC
ENCODE_FRAME_POINTER
@@ -1132,8 +1131,7 @@ ENTRY(xen_failsafe_callback)
UNWIND_HINT_IRET_REGS
pushq $-1 /* orig_ax = -1 => not a system call */
ALLOC_PT_GPREGS_ON_STACK
- SAVE_C_REGS
- SAVE_EXTRA_REGS
+ SAVE_REGS
CLEAR_REGS_NOSPEC
ENCODE_FRAME_POINTER
jmp error_exit
@@ -1178,8 +1176,7 @@ idtentry machine_check do_mce has_error_code=0 paranoid=1
ENTRY(paranoid_entry)
UNWIND_HINT_FUNC
cld
- SAVE_C_REGS 8
- SAVE_EXTRA_REGS 8
+ SAVE_REGS 8
CLEAR_REGS_NOSPEC
ENCODE_FRAME_POINTER 8
movl $1, %ebx
@@ -1231,8 +1228,7 @@ END(paranoid_exit)
ENTRY(error_entry)
UNWIND_HINT_FUNC
cld
- SAVE_C_REGS 8
- SAVE_EXTRA_REGS 8
+ SAVE_REGS 8
CLEAR_REGS_NOSPEC
ENCODE_FRAME_POINTER 8
testb $3, CS+8(%rsp)