From 9b61007695964aff339bb7ff40da33454e4d33d5 Mon Sep 17 00:00:00 2001
From: Thomas Gleixner <tglx@linutronix.de>
Date: Thu, 17 Mar 2011 11:32:28 +0100
Subject: [PATCH 047/278] mm: Fixup all fault handlers to check
 current->pagefault_disable

Necessary for decoupling pagefault disable from preempt count.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
 arch/alpha/mm/fault.c      |    2 +-
 arch/arm/mm/fault.c        |    2 +-
 arch/avr32/mm/fault.c      |    3 ++-
 arch/cris/mm/fault.c       |    2 +-
 arch/frv/mm/fault.c        |    2 +-
 arch/ia64/mm/fault.c       |    2 +-
 arch/m32r/mm/fault.c       |    2 +-
 arch/m68k/mm/fault.c       |    2 +-
 arch/microblaze/mm/fault.c |    2 +-
 arch/mips/mm/fault.c       |    2 +-
 arch/mn10300/mm/fault.c    |    2 +-
 arch/parisc/mm/fault.c     |    2 +-
 arch/powerpc/mm/fault.c    |    2 +-
 arch/s390/mm/fault.c       |    6 ++++--
 arch/score/mm/fault.c      |    2 +-
 arch/sh/mm/fault_32.c      |    2 +-
 arch/sparc/mm/fault_32.c   |    4 ++--
 arch/sparc/mm/fault_64.c   |    2 +-
 arch/tile/mm/fault.c       |    2 +-
 arch/um/kernel/trap.c      |    2 +-
 arch/x86/mm/fault.c        |    2 +-
 arch/xtensa/mm/fault.c     |    2 +-
 22 files changed, 27 insertions(+), 24 deletions(-)

diff --git a/arch/alpha/mm/fault.c b/arch/alpha/mm/fault.c
index fadd5f8..6d73e1b 100644
--- a/arch/alpha/mm/fault.c
+++ b/arch/alpha/mm/fault.c
@@ -107,7 +107,7 @@ do_page_fault(unsigned long address, unsigned long mmcsr,
 
 	/* If we're in an interrupt context, or have no user context,
 	   we must not take the fault.  */
-	if (!mm || in_atomic())
+	if (!mm || in_atomic() || current->pagefault_disabled)
 		goto no_context;
 
 #ifdef CONFIG_ALPHA_LARGE_VMALLOC
diff --git a/arch/arm/mm/fault.c b/arch/arm/mm/fault.c
index 4b0bc37..0fe9b9b 100644
--- a/arch/arm/mm/fault.c
+++ b/arch/arm/mm/fault.c
@@ -296,7 +296,7 @@ do_page_fault(unsigned long addr, unsigned int fsr, struct pt_regs *regs)
 	 * If we're in an interrupt or have no user
 	 * context, we must not take the fault..
 	 */
-	if (in_atomic() || !mm)
+	if (in_atomic() || !mm || current->pagefault_disabled)
 		goto no_context;
 
 	/*
diff --git a/arch/avr32/mm/fault.c b/arch/avr32/mm/fault.c
index f7040a1..623a027 100644
--- a/arch/avr32/mm/fault.c
+++ b/arch/avr32/mm/fault.c
@@ -81,7 +81,8 @@ asmlinkage void do_page_fault(unsigned long ecr, struct pt_regs *regs)
 	 * If we're in an interrupt or have no user context, we must
 	 * not take the fault...
 	 */
-	if (in_atomic() || !mm || regs->sr & SYSREG_BIT(GM))
+	if (in_atomic() || !mm || regs->sr & SYSREG_BIT(GM) ||
+	    current->pagefault_disabled)
 		goto no_context;
 
 	local_irq_enable();
diff --git a/arch/cris/mm/fault.c b/arch/cris/mm/fault.c
index 9dcac8e..2b2c292 100644
--- a/arch/cris/mm/fault.c
+++ b/arch/cris/mm/fault.c
@@ -111,7 +111,7 @@ do_page_fault(unsigned long address, struct pt_regs *regs,
 	 * user context, we must not take the fault.
 	 */
 
-	if (in_atomic() || !mm)
+	if (in_atomic() || !mm || current->pagefault_disabled)
 		goto no_context;
 
 	down_read(&mm->mmap_sem);
diff --git a/arch/frv/mm/fault.c b/arch/frv/mm/fault.c
index a325d57..3da8ec7 100644
--- a/arch/frv/mm/fault.c
+++ b/arch/frv/mm/fault.c
@@ -79,7 +79,7 @@ asmlinkage void do_page_fault(int datammu, unsigned long esr0, unsigned long ear
 	 * If we're in an interrupt or have no user
 	 * context, we must not take the fault..
 	 */
-	if (in_atomic() || !mm)
+	if (in_atomic() || !mm || current->pagefault_disabled)
 		goto no_context;
 
 	down_read(&mm->mmap_sem);
diff --git a/arch/ia64/mm/fault.c b/arch/ia64/mm/fault.c
index 20b3593..2a4e44f 100644
--- a/arch/ia64/mm/fault.c
+++ b/arch/ia64/mm/fault.c
@@ -89,7 +89,7 @@ ia64_do_page_fault (unsigned long address, unsigned long isr, struct pt_regs *re
 	/*
 	 * If we're in an interrupt or have no user context, we must not take the fault..
 	 */
-	if (in_atomic() || !mm)
+	if (in_atomic() || !mm || current->pagefault_disabled)
 		goto no_context;
 
 #ifdef CONFIG_VIRTUAL_MEM_MAP
diff --git a/arch/m32r/mm/fault.c b/arch/m32r/mm/fault.c
index 2c9aeb4..16fa2c7 100644
--- a/arch/m32r/mm/fault.c
+++ b/arch/m32r/mm/fault.c
@@ -115,7 +115,7 @@ asmlinkage void do_page_fault(struct pt_regs *regs, unsigned long error_code,
 	 * If we're in an interrupt or have no user context or are running in an
 	 * atomic region then we must not take the fault..
 	 */
-	if (in_atomic() || !mm)
+	if (in_atomic() || !mm || current->pagefault_disabled)
 		goto bad_area_nosemaphore;
 
 	/* When running in the kernel we expect faults to occur only to
diff --git a/arch/m68k/mm/fault.c b/arch/m68k/mm/fault.c
index 2db6099..238ffc0 100644
--- a/arch/m68k/mm/fault.c
+++ b/arch/m68k/mm/fault.c
@@ -85,7 +85,7 @@ int do_page_fault(struct pt_regs *regs, unsigned long address,
 	 * If we're in an interrupt or have no user
 	 * context, we must not take the fault..
 	 */
-	if (in_atomic() || !mm)
+	if (in_atomic() || !mm || current->pagefault_disabled)
 		goto no_context;
 
 	down_read(&mm->mmap_sem);
diff --git a/arch/microblaze/mm/fault.c b/arch/microblaze/mm/fault.c
index ae97d2c..c3f219c 100644
--- a/arch/microblaze/mm/fault.c
+++ b/arch/microblaze/mm/fault.c
@@ -107,7 +107,7 @@ void do_page_fault(struct pt_regs *regs, unsigned long address,
 	if ((error_code & 0x13) == 0x13 || (error_code & 0x11) == 0x11)
 		is_write = 0;
 
-	if (unlikely(in_atomic() || !mm)) {
+	if (unlikely(in_atomic() || !mm || current->pagefault_disabled)) {
 		if (kernel_mode(regs))
 			goto bad_area_nosemaphore;
 
diff --git a/arch/mips/mm/fault.c b/arch/mips/mm/fault.c
index 937cf33..ce7e75e 100644
--- a/arch/mips/mm/fault.c
+++ b/arch/mips/mm/fault.c
@@ -88,7 +88,7 @@ asmlinkage void __kprobes do_page_fault(struct pt_regs *regs, unsigned long writ
 	 * If we're in an interrupt or have no user
 	 * context, we must not take the fault..
 	 */
-	if (in_atomic() || !mm)
+	if (in_atomic() || !mm || current->pagefault_disabled)
 		goto bad_area_nosemaphore;
 
 	down_read(&mm->mmap_sem);
diff --git a/arch/mn10300/mm/fault.c b/arch/mn10300/mm/fault.c
index 0945409..53c8d16 100644
--- a/arch/mn10300/mm/fault.c
+++ b/arch/mn10300/mm/fault.c
@@ -168,7 +168,7 @@ asmlinkage void do_page_fault(struct pt_regs *regs, unsigned long fault_code,
 	 * If we're in an interrupt or have no user
 	 * context, we must not take the fault..
 	 */
-	if (in_atomic() || !mm)
+	if (in_atomic() || !mm || current->pagefault_disabled)
 		goto no_context;
 
 	down_read(&mm->mmap_sem);
diff --git a/arch/parisc/mm/fault.c b/arch/parisc/mm/fault.c
index 18162ce..09ecc8a 100644
--- a/arch/parisc/mm/fault.c
+++ b/arch/parisc/mm/fault.c
@@ -176,7 +176,7 @@ void do_page_fault(struct pt_regs *regs, unsigned long code,
 	unsigned long acc_type;
 	int fault;
 
-	if (in_atomic() || !mm)
+	if (in_atomic() || !mm || current->pagefault_disabled)
 		goto no_context;
 
 	down_read(&mm->mmap_sem);
diff --git a/arch/powerpc/mm/fault.c b/arch/powerpc/mm/fault.c
index 5efe8c9..17f8bbe 100644
--- a/arch/powerpc/mm/fault.c
+++ b/arch/powerpc/mm/fault.c
@@ -162,7 +162,7 @@ int __kprobes do_page_fault(struct pt_regs *regs, unsigned long address,
 	}
 #endif
 
-	if (in_atomic() || mm == NULL) {
+	if (in_atomic() || mm == NULL || current->pagefault_disabled) {
 		if (!user_mode(regs))
 			return SIGSEGV;
 		/* in_atomic() in user mode is really bad,
diff --git a/arch/s390/mm/fault.c b/arch/s390/mm/fault.c
index 0fc0a7e..b282958 100644
--- a/arch/s390/mm/fault.c
+++ b/arch/s390/mm/fault.c
@@ -294,7 +294,8 @@ static inline int do_exception(struct pt_regs *regs, int access,
 	 * user context.
 	 */
 	fault = VM_FAULT_BADCONTEXT;
-	if (unlikely(!user_space_fault(trans_exc_code) || in_atomic() || !mm))
+	if (unlikely(!user_space_fault(trans_exc_code) || in_atomic() || !mm ||
+		    tsk->pagefault_disabled))
 		goto out;
 
 	address = trans_exc_code & __FAIL_ADDR_MASK;
@@ -425,7 +426,8 @@ void __kprobes do_asce_exception(struct pt_regs *regs, long pgm_int_code,
 	struct mm_struct *mm = current->mm;
 	struct vm_area_struct *vma;
 
-	if (unlikely(!user_space_fault(trans_exc_code) || in_atomic() || !mm))
+	if (unlikely(!user_space_fault(trans_exc_code) || in_atomic() || !mm ||
+		     current->pagefault_disabled))
 		goto no_context;
 
 	down_read(&mm->mmap_sem);
diff --git a/arch/score/mm/fault.c b/arch/score/mm/fault.c
index 47b600e..4c12824 100644
--- a/arch/score/mm/fault.c
+++ b/arch/score/mm/fault.c
@@ -72,7 +72,7 @@ asmlinkage void do_page_fault(struct pt_regs *regs, unsigned long write,
 	* If we're in an interrupt or have no user
 	* context, we must not take the fault..
 	*/
-	if (in_atomic() || !mm)
+	if (in_atomic() || !mm || current->pagefault_disabled)
 		goto bad_area_nosemaphore;
 
 	down_read(&mm->mmap_sem);
diff --git a/arch/sh/mm/fault_32.c b/arch/sh/mm/fault_32.c
index 7bebd04..a67ac56 100644
--- a/arch/sh/mm/fault_32.c
+++ b/arch/sh/mm/fault_32.c
@@ -166,7 +166,7 @@ asmlinkage void __kprobes do_page_fault(struct pt_regs *regs,
 	 * If we're in an interrupt, have no user context or are running
 	 * in an atomic region then we must not take the fault:
 	 */
-	if (in_atomic() || !mm)
+	if (in_atomic() || !mm || current->pagefault_disabled)
 		goto no_context;
 
 	down_read(&mm->mmap_sem);
diff --git a/arch/sparc/mm/fault_32.c b/arch/sparc/mm/fault_32.c
index 8023fd7..e0742c1 100644
--- a/arch/sparc/mm/fault_32.c
+++ b/arch/sparc/mm/fault_32.c
@@ -247,8 +247,8 @@ asmlinkage void do_sparc_fault(struct pt_regs *regs, int text_fault, int write,
 	 * If we're in an interrupt or have no user
 	 * context, we must not take the fault..
 	 */
-        if (in_atomic() || !mm)
-                goto no_context;
+	if (in_atomic() || !mm || current->pagefault_disabled)
+		goto no_context;
 
 	perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, address);
 
diff --git a/arch/sparc/mm/fault_64.c b/arch/sparc/mm/fault_64.c
index 504c062..9d691a5 100644
--- a/arch/sparc/mm/fault_64.c
+++ b/arch/sparc/mm/fault_64.c
@@ -322,7 +322,7 @@ asmlinkage void __kprobes do_sparc64_fault(struct pt_regs *regs)
 	 * If we're in an interrupt or have no user
 	 * context, we must not take the fault..
 	 */
-	if (in_atomic() || !mm)
+	if (in_atomic() || !mm || current->pagefault_enabled)
 		goto intr_or_no_mm;
 
 	perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, address);
diff --git a/arch/tile/mm/fault.c b/arch/tile/mm/fault.c
index 25b7b90..ecdb016 100644
--- a/arch/tile/mm/fault.c
+++ b/arch/tile/mm/fault.c
@@ -346,7 +346,7 @@ static int handle_page_fault(struct pt_regs *regs,
 	 * If we're in an interrupt, have no user context or are running in an
 	 * atomic region then we must not take the fault.
 	 */
-	if (in_atomic() || !mm) {
+	if (in_atomic() || !mm || current->pagefault_disabled) {
 		vma = NULL;  /* happy compiler */
 		goto bad_area_nosemaphore;
 	}
diff --git a/arch/um/kernel/trap.c b/arch/um/kernel/trap.c
index dafc947..a283400 100644
--- a/arch/um/kernel/trap.c
+++ b/arch/um/kernel/trap.c
@@ -37,7 +37,7 @@ int handle_page_fault(unsigned long address, unsigned long ip,
 	 * If the fault was during atomic operation, don't take the fault, just
 	 * fail.
 	 */
-	if (in_atomic())
+	if (in_atomic() || !mm || current->pagefault_disabled)
 		goto out_nosemaphore;
 
 	down_read(&mm->mmap_sem);
diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c
index 5db0490..191015f 100644
--- a/arch/x86/mm/fault.c
+++ b/arch/x86/mm/fault.c
@@ -1084,7 +1084,7 @@ do_page_fault(struct pt_regs *regs, unsigned long error_code)
 	 * If we're in an interrupt, have no user context or are running
 	 * in an atomic region then we must not take the fault:
 	 */
-	if (unlikely(in_atomic() || !mm)) {
+	if (unlikely(in_atomic() || !mm || current->pagefault_disabled)) {
 		bad_area_nosemaphore(regs, error_code, address);
 		return;
 	}
diff --git a/arch/xtensa/mm/fault.c b/arch/xtensa/mm/fault.c
index e367e30..705f483 100644
--- a/arch/xtensa/mm/fault.c
+++ b/arch/xtensa/mm/fault.c
@@ -57,7 +57,7 @@ void do_page_fault(struct pt_regs *regs)
 	/* If we're in an interrupt or have no user
 	 * context, we must not take the fault..
 	 */
-	if (in_atomic() || !mm) {
+	if (in_atomic() || !mm || current->pagefault_disabled) {
 		bad_page_fault(regs, address, SIGSEGV);
 		return;
 	}
-- 
1.7.10