[PATCH 2/7] mm: Introduce FAULT_FLAG_DEFAULT
From: Peter Xu
Date: Fri Jun 28 2019 - 06:45:20 EST
Although there're tons of arch-specific page fault handlers, most of
them are still sharing the same initial value of the page fault flags.
Say, merely all of the page fault handlers would allow the fault to be
retried, and they also allow the fault to respond to SIGKILL.
Let's define a default value for the fault flags to replace those
initial page fault flags that were copied over. With this, it'll be
far easier to introduce new fault flag that can be used by all the
architectures instead of touching all the archs.
Signed-off-by: Peter Xu <peterx@xxxxxxxxxx>
---
arch/alpha/mm/fault.c | 2 +-
arch/arc/mm/fault.c | 2 +-
arch/arm/mm/fault.c | 2 +-
arch/arm64/mm/fault.c | 2 +-
arch/hexagon/mm/vm_fault.c | 2 +-
arch/ia64/mm/fault.c | 2 +-
arch/m68k/mm/fault.c | 2 +-
arch/microblaze/mm/fault.c | 2 +-
arch/mips/mm/fault.c | 2 +-
arch/nds32/mm/fault.c | 2 +-
arch/nios2/mm/fault.c | 2 +-
arch/openrisc/mm/fault.c | 2 +-
arch/parisc/mm/fault.c | 2 +-
arch/powerpc/mm/fault.c | 2 +-
arch/riscv/mm/fault.c | 2 +-
arch/s390/mm/fault.c | 2 +-
arch/sh/mm/fault.c | 2 +-
arch/sparc/mm/fault_32.c | 2 +-
arch/sparc/mm/fault_64.c | 2 +-
arch/um/kernel/trap.c | 2 +-
arch/unicore32/mm/fault.c | 2 +-
arch/x86/mm/fault.c | 2 +-
arch/xtensa/mm/fault.c | 2 +-
include/linux/mm.h | 7 +++++++
24 files changed, 30 insertions(+), 23 deletions(-)
diff --git a/arch/alpha/mm/fault.c b/arch/alpha/mm/fault.c
index 188fc9256baf..fceb684d3090 100644
--- a/arch/alpha/mm/fault.c
+++ b/arch/alpha/mm/fault.c
@@ -89,7 +89,7 @@ do_page_fault(unsigned long address, unsigned long mmcsr,
const struct exception_table_entry *fixup;
int si_code = SEGV_MAPERR;
vm_fault_t fault;
- unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE;
+ unsigned int flags = FAULT_FLAG_DEFAULT;
/* As of EV6, a load into $31/$f31 is a prefetch, and never faults
(or is suppressed by the PALcode). Support that for older CPUs
diff --git a/arch/arc/mm/fault.c b/arch/arc/mm/fault.c
index 8cca03480bb2..9f9b55d431ac 100644
--- a/arch/arc/mm/fault.c
+++ b/arch/arc/mm/fault.c
@@ -67,7 +67,7 @@ void do_page_fault(unsigned long address, struct pt_regs *regs)
int ret;
vm_fault_t fault;
int write = regs->ecr_cause & ECR_C_PROTV_STORE; /* ST/EX */
- unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE;
+ unsigned int flags = FAULT_FLAG_DEFAULT;
/*
* We fault-in kernel-space virtual memory on-demand. The
diff --git a/arch/arm/mm/fault.c b/arch/arm/mm/fault.c
index 0048eadd0681..d98af3169d69 100644
--- a/arch/arm/mm/fault.c
+++ b/arch/arm/mm/fault.c
@@ -261,7 +261,7 @@ do_page_fault(unsigned long addr, unsigned int fsr, struct pt_regs *regs)
struct mm_struct *mm;
int sig, code;
vm_fault_t fault;
- unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE;
+ unsigned int flags = FAULT_FLAG_DEFAULT;
if (notify_page_fault(regs, fsr))
return 0;
diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c
index 2d115016feb4..1cdd68e1c63c 100644
--- a/arch/arm64/mm/fault.c
+++ b/arch/arm64/mm/fault.c
@@ -433,7 +433,7 @@ static int __kprobes do_page_fault(unsigned long addr, unsigned int esr,
struct mm_struct *mm;
vm_fault_t fault, major = 0;
unsigned long vm_flags = VM_READ | VM_WRITE;
- unsigned int mm_flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE;
+ unsigned int mm_flags = FAULT_FLAG_DEFAULT;
if (notify_page_fault(regs, esr))
return 0;
diff --git a/arch/hexagon/mm/vm_fault.c b/arch/hexagon/mm/vm_fault.c
index b7a99aa5b0ba..c0411412ce3c 100644
--- a/arch/hexagon/mm/vm_fault.c
+++ b/arch/hexagon/mm/vm_fault.c
@@ -41,7 +41,7 @@ void do_page_fault(unsigned long address, long cause, struct pt_regs *regs)
int si_code = SEGV_MAPERR;
vm_fault_t fault;
const struct exception_table_entry *fixup;
- unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE;
+ unsigned int flags = FAULT_FLAG_DEFAULT;
/*
* If we're in an interrupt or have no user context,
diff --git a/arch/ia64/mm/fault.c b/arch/ia64/mm/fault.c
index 5baeb022f474..b01588e18079 100644
--- a/arch/ia64/mm/fault.c
+++ b/arch/ia64/mm/fault.c
@@ -87,7 +87,7 @@ ia64_do_page_fault (unsigned long address, unsigned long isr, struct pt_regs *re
struct mm_struct *mm = current->mm;
unsigned long mask;
vm_fault_t fault;
- unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE;
+ unsigned int flags = FAULT_FLAG_DEFAULT;
mask = ((((isr >> IA64_ISR_X_BIT) & 1UL) << VM_EXEC_BIT)
| (((isr >> IA64_ISR_W_BIT) & 1UL) << VM_WRITE_BIT));
diff --git a/arch/m68k/mm/fault.c b/arch/m68k/mm/fault.c
index 9b6163c05a75..22e4e6c68bfe 100644
--- a/arch/m68k/mm/fault.c
+++ b/arch/m68k/mm/fault.c
@@ -71,7 +71,7 @@ int do_page_fault(struct pt_regs *regs, unsigned long address,
struct mm_struct *mm = current->mm;
struct vm_area_struct * vma;
vm_fault_t fault;
- unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE;
+ unsigned int flags = FAULT_FLAG_DEFAULT;
pr_debug("do page fault:\nregs->sr=%#x, regs->pc=%#lx, address=%#lx, %ld, %p\n",
regs->sr, regs->pc, address, error_code, mm ? mm->pgd : NULL);
diff --git a/arch/microblaze/mm/fault.c b/arch/microblaze/mm/fault.c
index 202ad6a494f5..fff0e08ec7c6 100644
--- a/arch/microblaze/mm/fault.c
+++ b/arch/microblaze/mm/fault.c
@@ -91,7 +91,7 @@ void do_page_fault(struct pt_regs *regs, unsigned long address,
int code = SEGV_MAPERR;
int is_write = error_code & ESR_S;
vm_fault_t fault;
- unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE;
+ unsigned int flags = FAULT_FLAG_DEFAULT;
regs->ear = address;
regs->esr = error_code;
diff --git a/arch/mips/mm/fault.c b/arch/mips/mm/fault.c
index 73d8a0f0b810..5879dd93bf34 100644
--- a/arch/mips/mm/fault.c
+++ b/arch/mips/mm/fault.c
@@ -44,7 +44,7 @@ static void __kprobes __do_page_fault(struct pt_regs *regs, unsigned long write,
const int field = sizeof(unsigned long) * 2;
int si_code;
vm_fault_t fault;
- unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE;
+ unsigned int flags = FAULT_FLAG_DEFAULT;
static DEFINE_RATELIMIT_STATE(ratelimit_state, 5 * HZ, 10);
diff --git a/arch/nds32/mm/fault.c b/arch/nds32/mm/fault.c
index 68d5f2a27f38..875e254aaa7c 100644
--- a/arch/nds32/mm/fault.c
+++ b/arch/nds32/mm/fault.c
@@ -76,7 +76,7 @@ void do_page_fault(unsigned long entry, unsigned long addr,
int si_code;
vm_fault_t fault;
unsigned int mask = VM_READ | VM_WRITE | VM_EXEC;
- unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE;
+ unsigned int flags = FAULT_FLAG_DEFAULT;
error_code = error_code & (ITYPE_mskINST | ITYPE_mskETYPE);
tsk = current;
diff --git a/arch/nios2/mm/fault.c b/arch/nios2/mm/fault.c
index 6a2e716b959f..a401b45cae47 100644
--- a/arch/nios2/mm/fault.c
+++ b/arch/nios2/mm/fault.c
@@ -47,7 +47,7 @@ asmlinkage void do_page_fault(struct pt_regs *regs, unsigned long cause,
struct mm_struct *mm = tsk->mm;
int code = SEGV_MAPERR;
vm_fault_t fault;
- unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE;
+ unsigned int flags = FAULT_FLAG_DEFAULT;
cause >>= 2;
diff --git a/arch/openrisc/mm/fault.c b/arch/openrisc/mm/fault.c
index 9eee5bf3db27..ebdddcc1de60 100644
--- a/arch/openrisc/mm/fault.c
+++ b/arch/openrisc/mm/fault.c
@@ -50,7 +50,7 @@ asmlinkage void do_page_fault(struct pt_regs *regs, unsigned long address,
struct vm_area_struct *vma;
int si_code;
vm_fault_t fault;
- unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE;
+ unsigned int flags = FAULT_FLAG_DEFAULT;
tsk = current;
diff --git a/arch/parisc/mm/fault.c b/arch/parisc/mm/fault.c
index c8e8b7c05558..48cc1305850a 100644
--- a/arch/parisc/mm/fault.c
+++ b/arch/parisc/mm/fault.c
@@ -273,7 +273,7 @@ void do_page_fault(struct pt_regs *regs, unsigned long code,
if (!mm)
goto no_context;
- flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE;
+ flags = FAULT_FLAG_DEFAULT;
if (user_mode(regs))
flags |= FAULT_FLAG_USER;
diff --git a/arch/powerpc/mm/fault.c b/arch/powerpc/mm/fault.c
index ec6b7ad70659..6d86d6b52b73 100644
--- a/arch/powerpc/mm/fault.c
+++ b/arch/powerpc/mm/fault.c
@@ -456,7 +456,7 @@ static int __do_page_fault(struct pt_regs *regs, unsigned long address,
{
struct vm_area_struct * vma;
struct mm_struct *mm = current->mm;
- unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE;
+ unsigned int flags = FAULT_FLAG_DEFAULT;
int is_exec = TRAP(regs) == 0x400;
int is_user = user_mode(regs);
int is_write = page_fault_is_write(error_code);
diff --git a/arch/riscv/mm/fault.c b/arch/riscv/mm/fault.c
index 3e2708c626a8..a6b26c588ae6 100644
--- a/arch/riscv/mm/fault.c
+++ b/arch/riscv/mm/fault.c
@@ -28,7 +28,7 @@ asmlinkage void do_page_fault(struct pt_regs *regs)
struct vm_area_struct *vma;
struct mm_struct *mm;
unsigned long addr, cause;
- unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE;
+ unsigned int flags = FAULT_FLAG_DEFAULT;
int code = SEGV_MAPERR;
vm_fault_t fault;
diff --git a/arch/s390/mm/fault.c b/arch/s390/mm/fault.c
index df75d574246d..1717163e850a 100644
--- a/arch/s390/mm/fault.c
+++ b/arch/s390/mm/fault.c
@@ -442,7 +442,7 @@ static inline vm_fault_t do_exception(struct pt_regs *regs, int access)
address = trans_exc_code & __FAIL_ADDR_MASK;
perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, address);
- flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE;
+ flags = FAULT_FLAG_DEFAULT;
if (user_mode(regs))
flags |= FAULT_FLAG_USER;
if (access == VM_WRITE || (trans_exc_code & store_indication) == 0x400)
diff --git a/arch/sh/mm/fault.c b/arch/sh/mm/fault.c
index 6defd2c6d9b1..5ca9f80f18d3 100644
--- a/arch/sh/mm/fault.c
+++ b/arch/sh/mm/fault.c
@@ -397,7 +397,7 @@ asmlinkage void __kprobes do_page_fault(struct pt_regs *regs,
struct mm_struct *mm;
struct vm_area_struct * vma;
vm_fault_t fault;
- unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE;
+ unsigned int flags = FAULT_FLAG_DEFAULT;
tsk = current;
mm = tsk->mm;
diff --git a/arch/sparc/mm/fault_32.c b/arch/sparc/mm/fault_32.c
index b0440b0edd97..a2c9610e1666 100644
--- a/arch/sparc/mm/fault_32.c
+++ b/arch/sparc/mm/fault_32.c
@@ -168,7 +168,7 @@ asmlinkage void do_sparc_fault(struct pt_regs *regs, int text_fault, int write,
int from_user = !(regs->psr & PSR_PS);
int code;
vm_fault_t fault;
- unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE;
+ unsigned int flags = FAULT_FLAG_DEFAULT;
if (text_fault)
address = regs->pc;
diff --git a/arch/sparc/mm/fault_64.c b/arch/sparc/mm/fault_64.c
index 8f8a604c1300..89a3a7913854 100644
--- a/arch/sparc/mm/fault_64.c
+++ b/arch/sparc/mm/fault_64.c
@@ -281,7 +281,7 @@ asmlinkage void __kprobes do_sparc64_fault(struct pt_regs *regs)
int si_code, fault_code;
vm_fault_t fault;
unsigned long address, mm_rss;
- unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE;
+ unsigned int flags = FAULT_FLAG_DEFAULT;
fault_code = get_thread_fault_code();
diff --git a/arch/um/kernel/trap.c b/arch/um/kernel/trap.c
index 0e8b6158f224..9342ff15ac0d 100644
--- a/arch/um/kernel/trap.c
+++ b/arch/um/kernel/trap.c
@@ -32,7 +32,7 @@ int handle_page_fault(unsigned long address, unsigned long ip,
pmd_t *pmd;
pte_t *pte;
int err = -EFAULT;
- unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE;
+ unsigned int flags = FAULT_FLAG_DEFAULT;
*code_out = SEGV_MAPERR;
diff --git a/arch/unicore32/mm/fault.c b/arch/unicore32/mm/fault.c
index 33e0d8a267e8..0516c72ae702 100644
--- a/arch/unicore32/mm/fault.c
+++ b/arch/unicore32/mm/fault.c
@@ -201,7 +201,7 @@ static int do_pf(unsigned long addr, unsigned int fsr, struct pt_regs *regs)
struct mm_struct *mm;
int sig, code;
vm_fault_t fault;
- unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE;
+ unsigned int flags = FAULT_FLAG_DEFAULT;
tsk = current;
mm = tsk->mm;
diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c
index 46df4c6aae46..0b0d7737972a 100644
--- a/arch/x86/mm/fault.c
+++ b/arch/x86/mm/fault.c
@@ -1305,7 +1305,7 @@ void do_user_addr_fault(struct pt_regs *regs,
struct task_struct *tsk;
struct mm_struct *mm;
vm_fault_t fault, major = 0;
- unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE;
+ unsigned int flags = FAULT_FLAG_DEFAULT;
tsk = current;
mm = tsk->mm;
diff --git a/arch/xtensa/mm/fault.c b/arch/xtensa/mm/fault.c
index 2ab0e0dcd166..d16b0607f147 100644
--- a/arch/xtensa/mm/fault.c
+++ b/arch/xtensa/mm/fault.c
@@ -43,7 +43,7 @@ void do_page_fault(struct pt_regs *regs)
int is_write, is_exec;
vm_fault_t fault;
- unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE;
+ unsigned int flags = FAULT_FLAG_DEFAULT;
code = SEGV_MAPERR;
diff --git a/include/linux/mm.h b/include/linux/mm.h
index dd0b5f4e1e45..8eb796f2fa19 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -393,6 +393,13 @@ extern pgprot_t protection_map[16];
#define FAULT_FLAG_REMOTE 0x80 /* faulting for non current tsk/mm */
#define FAULT_FLAG_INSTRUCTION 0x100 /* The fault was during an instruction fetch */
+/*
+ * The default fault flags that should be used by most of the
+ * arch-specific page fault handlers.
+ */
+#define FAULT_FLAG_DEFAULT (FAULT_FLAG_ALLOW_RETRY | \
+ FAULT_FLAG_KILLABLE)
+
#define FAULT_FLAG_TRACE \
{ FAULT_FLAG_WRITE, "WRITE" }, \
{ FAULT_FLAG_MKWRITE, "MKWRITE" }, \
--
2.21.0