From: Alexander van Heukelum <heukelum@fastmail.fm>
To: Andy Lutomirski <luto@amacapital.net>,
x86@kernel.org, linux-kernel@vger.kernel.org
Cc: Frederic Weisbecker <fweisbec@gmail.com>,
Oleg Nesterov <oleg@redhat.com>, Borislav Petkov <bp@suse.de>,
Rik van Riel <riel@redhat.com>
Subject: [PATCHv2 1/4] x86_64: cleanup THREAD_INFO(reg,offset) macro
Date: Sun, 18 Jan 2015 12:45:17 +0100 [thread overview]
Message-ID: <1421581520-2816-2-git-send-email-heukelum@fastmail.fm> (raw)
In-Reply-To: <1421581520-2816-1-git-send-email-heukelum@fastmail.fm>
The macro THREAD_INFO(reg,offset) is used in assembly to compute the
offset between the user ptregs and the thread_info struct. Change
the macro and all its uses so that offset is given as the current
top of stack in the pt_regs frame. The generated code is identical.
Signed-off-by: Alexander van Heukelum <heukelum@fastmail.fm>
---
arch/x86/ia32/ia32entry.S | 30 +++++++++++++++---------------
arch/x86/include/asm/calling.h | 1 +
arch/x86/include/asm/thread_info.h | 2 +-
arch/x86/kernel/entry_64.S | 4 ++--
4 files changed, 19 insertions(+), 18 deletions(-)
diff --git a/arch/x86/ia32/ia32entry.S b/arch/x86/ia32/ia32entry.S
index 156ebca..1c74f39 100644
--- a/arch/x86/ia32/ia32entry.S
+++ b/arch/x86/ia32/ia32entry.S
@@ -135,7 +135,7 @@ ENTRY(ia32_sysenter_target)
CFI_REL_OFFSET rsp,0
pushfq_cfi
/*CFI_REL_OFFSET rflags,0*/
- movl TI_sysenter_return+THREAD_INFO(%rsp,3*8-KERNEL_STACK_OFFSET),%r10d
+ movl TI_sysenter_return+THREAD_INFO(%rsp,EFLAGS),%r10d
CFI_REGISTER rip,r10
pushq_cfi $__USER32_CS
/*CFI_REL_OFFSET cs,0*/
@@ -161,8 +161,8 @@ ENTRY(ia32_sysenter_target)
jnz sysenter_fix_flags
sysenter_flags_fixed:
- orl $TS_COMPAT,TI_status+THREAD_INFO(%rsp,RIP-ARGOFFSET)
- testl $_TIF_WORK_SYSCALL_ENTRY,TI_flags+THREAD_INFO(%rsp,RIP-ARGOFFSET)
+ orl $TS_COMPAT,TI_status+THREAD_INFO(%rsp,ARGOFFSET)
+ testl $_TIF_WORK_SYSCALL_ENTRY,TI_flags+THREAD_INFO(%rsp,ARGOFFSET)
CFI_REMEMBER_STATE
jnz sysenter_tracesys
cmpq $(IA32_NR_syscalls-1),%rax
@@ -174,10 +174,10 @@ sysenter_dispatch:
movq %rax,RAX-ARGOFFSET(%rsp)
DISABLE_INTERRUPTS(CLBR_NONE)
TRACE_IRQS_OFF
- testl $_TIF_ALLWORK_MASK,TI_flags+THREAD_INFO(%rsp,RIP-ARGOFFSET)
+ testl $_TIF_ALLWORK_MASK,TI_flags+THREAD_INFO(%rsp,ARGOFFSET)
jnz sysexit_audit
sysexit_from_sys_call:
- andl $~TS_COMPAT,TI_status+THREAD_INFO(%rsp,RIP-ARGOFFSET)
+ andl $~TS_COMPAT,TI_status+THREAD_INFO(%rsp,ARGOFFSET)
/* clear IF, that popfq doesn't enable interrupts early */
andl $~0x200,EFLAGS-ARGOFFSET(%rsp)
movl RIP-ARGOFFSET(%rsp),%edx /* User %eip */
@@ -216,7 +216,7 @@ sysexit_from_sys_call:
.endm
.macro auditsys_exit exit
- testl $(_TIF_ALLWORK_MASK & ~_TIF_SYSCALL_AUDIT),TI_flags+THREAD_INFO(%rsp,RIP-ARGOFFSET)
+ testl $(_TIF_ALLWORK_MASK & ~_TIF_SYSCALL_AUDIT),TI_flags+THREAD_INFO(%rsp,ARGOFFSET)
jnz ia32_ret_from_sys_call
TRACE_IRQS_ON
ENABLE_INTERRUPTS(CLBR_NONE)
@@ -231,7 +231,7 @@ sysexit_from_sys_call:
movl $(_TIF_ALLWORK_MASK & ~_TIF_SYSCALL_AUDIT),%edi
DISABLE_INTERRUPTS(CLBR_NONE)
TRACE_IRQS_OFF
- testl %edi,TI_flags+THREAD_INFO(%rsp,RIP-ARGOFFSET)
+ testl %edi,TI_flags+THREAD_INFO(%rsp,ARGOFFSET)
jz \exit
CLEAR_RREGS -ARGOFFSET
jmp int_with_check
@@ -253,7 +253,7 @@ sysenter_fix_flags:
sysenter_tracesys:
#ifdef CONFIG_AUDITSYSCALL
- testl $(_TIF_WORK_SYSCALL_ENTRY & ~_TIF_SYSCALL_AUDIT),TI_flags+THREAD_INFO(%rsp,RIP-ARGOFFSET)
+ testl $(_TIF_WORK_SYSCALL_ENTRY & ~_TIF_SYSCALL_AUDIT),TI_flags+THREAD_INFO(%rsp,ARGOFFSET)
jz sysenter_auditsys
#endif
SAVE_REST
@@ -324,8 +324,8 @@ ENTRY(ia32_cstar_target)
1: movl (%r8),%r9d
_ASM_EXTABLE(1b,ia32_badarg)
ASM_CLAC
- orl $TS_COMPAT,TI_status+THREAD_INFO(%rsp,RIP-ARGOFFSET)
- testl $_TIF_WORK_SYSCALL_ENTRY,TI_flags+THREAD_INFO(%rsp,RIP-ARGOFFSET)
+ orl $TS_COMPAT,TI_status+THREAD_INFO(%rsp,ARGOFFSET)
+ testl $_TIF_WORK_SYSCALL_ENTRY,TI_flags+THREAD_INFO(%rsp,ARGOFFSET)
CFI_REMEMBER_STATE
jnz cstar_tracesys
cmpq $IA32_NR_syscalls-1,%rax
@@ -337,10 +337,10 @@ cstar_dispatch:
movq %rax,RAX-ARGOFFSET(%rsp)
DISABLE_INTERRUPTS(CLBR_NONE)
TRACE_IRQS_OFF
- testl $_TIF_ALLWORK_MASK,TI_flags+THREAD_INFO(%rsp,RIP-ARGOFFSET)
+ testl $_TIF_ALLWORK_MASK,TI_flags+THREAD_INFO(%rsp,ARGOFFSET)
jnz sysretl_audit
sysretl_from_sys_call:
- andl $~TS_COMPAT,TI_status+THREAD_INFO(%rsp,RIP-ARGOFFSET)
+ andl $~TS_COMPAT,TI_status+THREAD_INFO(%rsp,ARGOFFSET)
RESTORE_ARGS 0,-ARG_SKIP,0,0,0
movl RIP-ARGOFFSET(%rsp),%ecx
CFI_REGISTER rip,rcx
@@ -368,7 +368,7 @@ sysretl_audit:
cstar_tracesys:
#ifdef CONFIG_AUDITSYSCALL
- testl $(_TIF_WORK_SYSCALL_ENTRY & ~_TIF_SYSCALL_AUDIT),TI_flags+THREAD_INFO(%rsp,RIP-ARGOFFSET)
+ testl $(_TIF_WORK_SYSCALL_ENTRY & ~_TIF_SYSCALL_AUDIT),TI_flags+THREAD_INFO(%rsp,ARGOFFSET)
jz cstar_auditsys
#endif
xchgl %r9d,%ebp
@@ -434,8 +434,8 @@ ENTRY(ia32_syscall)
/* note the registers are not zero extended to the sf.
this could be a problem. */
SAVE_ARGS 0,1,0
- orl $TS_COMPAT,TI_status+THREAD_INFO(%rsp,RIP-ARGOFFSET)
- testl $_TIF_WORK_SYSCALL_ENTRY,TI_flags+THREAD_INFO(%rsp,RIP-ARGOFFSET)
+ orl $TS_COMPAT,TI_status+THREAD_INFO(%rsp,ARGOFFSET)
+ testl $_TIF_WORK_SYSCALL_ENTRY,TI_flags+THREAD_INFO(%rsp,ARGOFFSET)
jnz ia32_tracesys
cmpq $(IA32_NR_syscalls-1),%rax
ja ia32_badsys
diff --git a/arch/x86/include/asm/calling.h b/arch/x86/include/asm/calling.h
index 1f1297b..16ab13d 100644
--- a/arch/x86/include/asm/calling.h
+++ b/arch/x86/include/asm/calling.h
@@ -81,6 +81,7 @@ For 32-bit we have the following conventions - kernel is built with
#define EFLAGS 144
#define RSP 152
#define SS 160
+#define PTREGS_SIZE 168
#define ARGOFFSET R11
diff --git a/arch/x86/include/asm/thread_info.h b/arch/x86/include/asm/thread_info.h
index e82e95a..471037d 100644
--- a/arch/x86/include/asm/thread_info.h
+++ b/arch/x86/include/asm/thread_info.h
@@ -190,7 +190,7 @@ static inline unsigned long current_stack_pointer(void)
* Same if PER_CPU_VAR(kernel_stack) is, perhaps with some offset, already in
* a certain register (to be used in assembler memory operands).
*/
-#define THREAD_INFO(reg, off) KERNEL_STACK_OFFSET+(off)-THREAD_SIZE(reg)
+#define THREAD_INFO(reg, off) PTREGS_SIZE-(off)-THREAD_SIZE(reg)
#endif
diff --git a/arch/x86/kernel/entry_64.S b/arch/x86/kernel/entry_64.S
index db13655..9f9ca20 100644
--- a/arch/x86/kernel/entry_64.S
+++ b/arch/x86/kernel/entry_64.S
@@ -343,7 +343,7 @@ GLOBAL(system_call_after_swapgs)
movq_cfi rax,(ORIG_RAX-ARGOFFSET)
movq %rcx,RIP-ARGOFFSET(%rsp)
CFI_REL_OFFSET rip,RIP-ARGOFFSET
- testl $_TIF_WORK_SYSCALL_ENTRY,TI_flags+THREAD_INFO(%rsp,RIP-ARGOFFSET)
+ testl $_TIF_WORK_SYSCALL_ENTRY,TI_flags+THREAD_INFO(%rsp,ARGOFFSET)
jnz tracesys
system_call_fastpath:
#if __SYSCALL_MASK == ~0
@@ -361,7 +361,7 @@ system_call_fastpath:
* Has incomplete stack frame and undefined top of stack.
*/
ret_from_sys_call:
- testl $_TIF_ALLWORK_MASK,TI_flags+THREAD_INFO(%rsp,RIP-ARGOFFSET)
+ testl $_TIF_ALLWORK_MASK,TI_flags+THREAD_INFO(%rsp,ARGOFFSET)
jnz int_ret_from_sys_call_fixup /* Go the the slow path */
LOCKDEP_SYS_EXIT
--
2.1.0
next prev parent reply other threads:[~2015-01-18 11:46 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-01-18 11:45 [PATCHv2 0/4] x86, entry: some cleanup and simplification Alexander van Heukelum
2015-01-18 11:45 ` Alexander van Heukelum [this message]
2015-01-21 13:40 ` [PATCHv2 1/4] x86_64: cleanup THREAD_INFO(reg,offset) macro Denys Vlasenko
2015-01-21 16:20 ` Alexander van Heukelum
2015-01-21 18:04 ` Borislav Petkov
2015-01-21 18:48 ` Alexander van Heukelum
2015-01-18 11:45 ` [PATCHv2 2/4] x86_64: embrace KERNEL_STACK_OFFSET Alexander van Heukelum
2015-01-21 13:44 ` Denys Vlasenko
2015-01-21 16:29 ` Alexander van Heukelum
2015-01-23 0:53 ` Denys Vlasenko
2015-01-18 11:45 ` [PATCHv2 3/4] i386: clean up KERNEL_STACK_OFFSET Alexander van Heukelum
2015-01-18 11:45 ` [PATCHv2 4/4] x86_64, entry: Create IRET-compatible stack frame at syscall entry Alexander van Heukelum
2015-01-18 16:38 ` Andy Lutomirski
2015-01-18 17:22 ` Alexander van Heukelum
2015-01-18 12:05 ` [PATCHv2 0/4] x86, entry: some cleanup and simplification Borislav Petkov
2015-01-18 15:47 ` Alexander van Heukelum
2015-01-21 13:26 ` Denys Vlasenko
2015-01-21 15:51 ` Alexander van Heukelum
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