mm/fault: convert remaining simple cases to lock_mm_and_find_vma()

This does the simple pattern conversion of alpha, arc, csky, hexagon,
loongarch, nios2, sh, sparc32, and xtensa to the lock_mm_and_find_vma()
helper.  They all have the regular fault handling pattern without odd
special cases.

The remaining architectures all have something that keeps us from a
straightforward conversion: ia64 and parisc have stacks that can grow
both up as well as down (and ia64 has special address region checks).

And m68k, microblaze, openrisc, sparc64, and um end up having extra
rules about only expanding the stack down a limited amount below the
user space stack pointer.  That is something that x86 used to do too
(long long ago), and it probably could just be skipped, but it still
makes the conversion less than trivial.

Note that this conversion was done manually and with the exception of
alpha without any build testing, because I have a fairly limited cross-
building environment.  The cases are all simple, and I went through the
changes several times, but...

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/arch/alpha/Kconfig b/arch/alpha/Kconfig
index a5c2b1aa46b02edbea92c2fea1d76d0d7e4e887c..d6968d090d49a7b9abe3a8ec1a8f446910ed2447 100644 (file)
--- a/arch/alpha/Kconfig
+++ b/arch/alpha/Kconfig
@@ -30,6 +30,7 @@ config ALPHA
        select HAS_IOPORT
        select HAVE_ARCH_AUDITSYSCALL
        select HAVE_MOD_ARCH_SPECIFIC
+       select LOCK_MM_AND_FIND_VMA
        select MODULES_USE_ELF_RELA
        select ODD_RT_SIGACTION
        select OLD_SIGSUSPEND

diff --git a/arch/alpha/mm/fault.c b/arch/alpha/mm/fault.c
index 7b01ae4f3bc6c7ab53dfb0c219c6fd75e2ffdf36..8c9850437e674451576c27388e0f6fe7b8780758 100644 (file)
--- a/arch/alpha/mm/fault.c
+++ b/arch/alpha/mm/fault.c
@@ -119,20 +119,12 @@ do_page_fault(unsigned long address, unsigned long mmcsr,
                flags |= FAULT_FLAG_USER;
        perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, address);
 retry:
-       mmap_read_lock(mm);
-       vma = find_vma(mm, address);
+       vma = lock_mm_and_find_vma(mm, address, regs);
        if (!vma)
-               goto bad_area;
-       if (vma->vm_start <= address)
-               goto good_area;
-       if (!(vma->vm_flags & VM_GROWSDOWN))
-               goto bad_area;
-       if (expand_stack(vma, address))
-               goto bad_area;
+               goto bad_area_nosemaphore;
 
        /* Ok, we have a good vm_area for this memory access, so
           we can handle it.  */
- good_area:
        si_code = SEGV_ACCERR;
        if (cause < 0) {
                if (!(vma->vm_flags & VM_EXEC))
@@ -192,6 +184,7 @@ retry:
  bad_area:
        mmap_read_unlock(mm);
 
+ bad_area_nosemaphore:
        if (user_mode(regs))
                goto do_sigsegv;
 

diff --git a/arch/arc/Kconfig b/arch/arc/Kconfig
index ab6d701365bb00c44420d397aa5115555e6bb4d9..96cf8720bb93910d3171c2fbe89d127166bbab23 100644 (file)
--- a/arch/arc/Kconfig
+++ b/arch/arc/Kconfig
@@ -41,6 +41,7 @@ config ARC
        select HAVE_PERF_EVENTS
        select HAVE_SYSCALL_TRACEPOINTS
        select IRQ_DOMAIN
+       select LOCK_MM_AND_FIND_VMA
        select MODULES_USE_ELF_RELA
        select OF
        select OF_EARLY_FLATTREE

diff --git a/arch/arc/mm/fault.c b/arch/arc/mm/fault.c
index 5ca59a482632a880f0a40d31c44d9b1159581b85..f59e722d147f91972ac8cf42b1f77d1a12cca80b 100644 (file)
--- a/arch/arc/mm/fault.c
+++ b/arch/arc/mm/fault.c
@@ -113,15 +113,9 @@ void do_page_fault(unsigned long address, struct pt_regs *regs)
 
        perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, address);
 retry:
-       mmap_read_lock(mm);
-
-       vma = find_vma(mm, address);
+       vma = lock_mm_and_find_vma(mm, address, regs);
        if (!vma)
-               goto bad_area;
-       if (unlikely(address < vma->vm_start)) {
-               if (!(vma->vm_flags & VM_GROWSDOWN) || expand_stack(vma, address))
-                       goto bad_area;
-       }
+               goto bad_area_nosemaphore;
 
        /*
         * vm_area is good, now check permissions for this memory access
@@ -161,6 +155,7 @@ retry:
 bad_area:
        mmap_read_unlock(mm);
 
+bad_area_nosemaphore:
        /*
         * Major/minor page fault accounting
         * (in case of retry we only land here once)

diff --git a/arch/csky/Kconfig b/arch/csky/Kconfig
index 4df1f8c9d170b3359d3759d1ce1640bf76a422af..03e9f66661570a755f4237f294a37912e504738e 100644 (file)
--- a/arch/csky/Kconfig
+++ b/arch/csky/Kconfig
@@ -96,6 +96,7 @@ config CSKY
        select HAVE_REGS_AND_STACK_ACCESS_API
        select HAVE_STACKPROTECTOR
        select HAVE_SYSCALL_TRACEPOINTS
+       select LOCK_MM_AND_FIND_VMA
        select MAY_HAVE_SPARSE_IRQ
        select MODULES_USE_ELF_RELA if MODULES
        select OF

diff --git a/arch/csky/mm/fault.c b/arch/csky/mm/fault.c
index e15f736cca4b4a43fb14989e099051fbdbf0a082..ae9781b7d92ea5e65554d42d6d9d6ba2ac5838d6 100644 (file)
--- a/arch/csky/mm/fault.c
+++ b/arch/csky/mm/fault.c
@@ -97,13 +97,12 @@ static inline void mm_fault_error(struct pt_regs *regs, unsigned long addr, vm_f
        BUG();
 }
 
-static inline void bad_area(struct pt_regs *regs, struct mm_struct *mm, int code, unsigned long addr)
+static inline void bad_area_nosemaphore(struct pt_regs *regs, struct mm_struct *mm, int code, unsigned long addr)
 {
        /*
         * Something tried to access memory that isn't in our memory map.
         * Fix it, but check if it's kernel or user first.
         */
-       mmap_read_unlock(mm);
        /* User mode accesses just cause a SIGSEGV */
        if (user_mode(regs)) {
                do_trap(regs, SIGSEGV, code, addr);
@@ -238,20 +237,9 @@ asmlinkage void do_page_fault(struct pt_regs *regs)
        if (is_write(regs))
                flags |= FAULT_FLAG_WRITE;
 retry:
-       mmap_read_lock(mm);
-       vma = find_vma(mm, addr);
+       vma = lock_mm_and_find_vma(mm, address, regs);
        if (unlikely(!vma)) {
-               bad_area(regs, mm, code, addr);
-               return;
-       }
-       if (likely(vma->vm_start <= addr))
-               goto good_area;
-       if (unlikely(!(vma->vm_flags & VM_GROWSDOWN))) {
-               bad_area(regs, mm, code, addr);
-               return;
-       }
-       if (unlikely(expand_stack(vma, addr))) {
-               bad_area(regs, mm, code, addr);
+               bad_area_nosemaphore(regs, mm, code, addr);
                return;
        }
 
@@ -259,11 +247,11 @@ retry:
         * Ok, we have a good vm_area for this memory access, so
         * we can handle it.
         */
-good_area:
        code = SEGV_ACCERR;
 
        if (unlikely(access_error(regs, vma))) {
-               bad_area(regs, mm, code, addr);
+               mmap_read_unlock(mm);
+               bad_area_nosemaphore(regs, mm, code, addr);
                return;
        }
 

diff --git a/arch/hexagon/Kconfig b/arch/hexagon/Kconfig
index 54eadf26517868f8cd575a1d5b777be700e35354..6726f4941015f353624a81838f6368c85508a0a7 100644 (file)
--- a/arch/hexagon/Kconfig
+++ b/arch/hexagon/Kconfig
@@ -28,6 +28,7 @@ config HEXAGON
        select GENERIC_SMP_IDLE_THREAD
        select STACKTRACE_SUPPORT
        select GENERIC_CLOCKEVENTS_BROADCAST
+       select LOCK_MM_AND_FIND_VMA
        select MODULES_USE_ELF_RELA
        select GENERIC_CPU_DEVICES
        select ARCH_WANT_LD_ORPHAN_WARN

diff --git a/arch/hexagon/mm/vm_fault.c b/arch/hexagon/mm/vm_fault.c
index 4b578d02fd01a9eb1513d34b708a84f6e5af31b5..7295ea3f8cc8d3c6f7cdec6fdcded75f11facb7a 100644 (file)
--- a/arch/hexagon/mm/vm_fault.c
+++ b/arch/hexagon/mm/vm_fault.c
@@ -57,21 +57,10 @@ void do_page_fault(unsigned long address, long cause, struct pt_regs *regs)
 
        perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, address);
 retry:
-       mmap_read_lock(mm);
-       vma = find_vma(mm, address);
-       if (!vma)
-               goto bad_area;
+       vma = lock_mm_and_find_vma(mm, address, regs);
+       if (unlikely(!vma))
+               goto bad_area_nosemaphore;
 
-       if (vma->vm_start <= address)
-               goto good_area;
-
-       if (!(vma->vm_flags & VM_GROWSDOWN))
-               goto bad_area;
-
-       if (expand_stack(vma, address))
-               goto bad_area;
-
-good_area:
        /* Address space is OK.  Now check access rights. */
        si_code = SEGV_ACCERR;
 
@@ -143,6 +132,7 @@ good_area:
 bad_area:
        mmap_read_unlock(mm);
 
+bad_area_nosemaphore:
        if (user_mode(regs)) {
                force_sig_fault(SIGSEGV, si_code, (void __user *)address);
                return;

diff --git a/arch/loongarch/Kconfig b/arch/loongarch/Kconfig
index d38b066fc931bc31758ee12d3c3800b6154d0641..73519e13bbb3940fd99f43720e80cc37b1025e29 100644 (file)
--- a/arch/loongarch/Kconfig
+++ b/arch/loongarch/Kconfig
@@ -130,6 +130,7 @@ config LOONGARCH
        select HAVE_VIRT_CPU_ACCOUNTING_GEN if !SMP
        select IRQ_FORCED_THREADING
        select IRQ_LOONGARCH_CPU
+       select LOCK_MM_AND_FIND_VMA
        select MMU_GATHER_MERGE_VMAS if MMU
        select MODULES_USE_ELF_RELA if MODULES
        select NEED_PER_CPU_EMBED_FIRST_CHUNK

diff --git a/arch/loongarch/mm/fault.c b/arch/loongarch/mm/fault.c
index 449087bd589d339dba1b27f66cc07f170085cff7..da5b6d518cdb1d6c5ec550083f52f588ccf29066 100644 (file)
--- a/arch/loongarch/mm/fault.c
+++ b/arch/loongarch/mm/fault.c
@@ -169,22 +169,18 @@ static void __kprobes __do_page_fault(struct pt_regs *regs,
 
        perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, address);
 retry:
-       mmap_read_lock(mm);
-       vma = find_vma(mm, address);
-       if (!vma)
-               goto bad_area;
-       if (vma->vm_start <= address)
-               goto good_area;
-       if (!(vma->vm_flags & VM_GROWSDOWN))
-               goto bad_area;
-       if (!expand_stack(vma, address))
-               goto good_area;
+       vma = lock_mm_and_find_vma(mm, address, regs);
+       if (unlikely(!vma))
+               goto bad_area_nosemaphore;
+       goto good_area;
+
 /*
  * Something tried to access memory that isn't in our memory map..
  * Fix it, but check if it's kernel or user first..
  */
 bad_area:
        mmap_read_unlock(mm);
+bad_area_nosemaphore:
        do_sigsegv(regs, write, address, si_code);
        return;
 

diff --git a/arch/nios2/Kconfig b/arch/nios2/Kconfig
index e5936417d3cd3ced8cb159d477202e23da5b54bc..d54464021a618ecd20c7bd23cbf52bce65208592 100644 (file)
--- a/arch/nios2/Kconfig
+++ b/arch/nios2/Kconfig
@@ -16,6 +16,7 @@ config NIOS2
        select HAVE_ARCH_TRACEHOOK
        select HAVE_ARCH_KGDB
        select IRQ_DOMAIN
+       select LOCK_MM_AND_FIND_VMA
        select MODULES_USE_ELF_RELA
        select OF
        select OF_EARLY_FLATTREE

diff --git a/arch/nios2/mm/fault.c b/arch/nios2/mm/fault.c
index ca64eccea5511d223add396c5f92d486703858b0..e3fa9c15181df23e01085416dec3de5e41b922cf 100644 (file)
--- a/arch/nios2/mm/fault.c
+++ b/arch/nios2/mm/fault.c
@@ -86,27 +86,14 @@ asmlinkage void do_page_fault(struct pt_regs *regs, unsigned long cause,
 
        perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, address);
 
-       if (!mmap_read_trylock(mm)) {
-               if (!user_mode(regs) && !search_exception_tables(regs->ea))
-                       goto bad_area_nosemaphore;
 retry:
-               mmap_read_lock(mm);
-       }
-
-       vma = find_vma(mm, address);
+       vma = lock_mm_and_find_vma(mm, address, regs);
        if (!vma)
-               goto bad_area;
-       if (vma->vm_start <= address)
-               goto good_area;
-       if (!(vma->vm_flags & VM_GROWSDOWN))
-               goto bad_area;
-       if (expand_stack(vma, address))
-               goto bad_area;
+               goto bad_area_nosemaphore;
 /*
  * Ok, we have a good vm_area for this memory access, so
  * we can handle it..
  */
-good_area:
        code = SEGV_ACCERR;
 
        switch (cause) {

diff --git a/arch/sh/Kconfig b/arch/sh/Kconfig
index 9652d367fc37771863e57369c94ab9489f080f87..393023d092450f0fe994d2e953ac5dd9a18b2624 100644 (file)
--- a/arch/sh/Kconfig
+++ b/arch/sh/Kconfig
@@ -59,6 +59,7 @@ config SUPERH
        select HAVE_STACKPROTECTOR
        select HAVE_SYSCALL_TRACEPOINTS
        select IRQ_FORCED_THREADING
+       select LOCK_MM_AND_FIND_VMA
        select MODULES_USE_ELF_RELA
        select NEED_SG_DMA_LENGTH
        select NO_DMA if !MMU && !DMA_COHERENT

diff --git a/arch/sh/mm/fault.c b/arch/sh/mm/fault.c
index acd2f5e50bfcd08ccb71fc71a8f33a1c9cb84c06..06e6b49529245a58bce87aef5caaeb0e5051357d 100644 (file)
--- a/arch/sh/mm/fault.c
+++ b/arch/sh/mm/fault.c
@@ -439,21 +439,9 @@ asmlinkage void __kprobes do_page_fault(struct pt_regs *regs,
        }
 
 retry:
-       mmap_read_lock(mm);
-
-       vma = find_vma(mm, address);
+       vma = lock_mm_and_find_vma(mm, address, regs);
        if (unlikely(!vma)) {
-               bad_area(regs, error_code, address);
-               return;
-       }
-       if (likely(vma->vm_start <= address))
-               goto good_area;
-       if (unlikely(!(vma->vm_flags & VM_GROWSDOWN))) {
-               bad_area(regs, error_code, address);
-               return;
-       }
-       if (unlikely(expand_stack(vma, address))) {
-               bad_area(regs, error_code, address);
+               bad_area_nosemaphore(regs, error_code, address);
                return;
        }
 
@@ -461,7 +449,6 @@ retry:
         * Ok, we have a good vm_area for this memory access, so
         * we can handle it..
         */
-good_area:
        if (unlikely(access_error(error_code, vma))) {
                bad_area_access_error(regs, error_code, address);
                return;

diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig
index 8535e19062f65fa99cbe380e4ea4f02422d28954..8c196990558b244b019e09fa73ce4d777e774e4f 100644 (file)
--- a/arch/sparc/Kconfig
+++ b/arch/sparc/Kconfig
@@ -57,6 +57,7 @@ config SPARC32
        select DMA_DIRECT_REMAP
        select GENERIC_ATOMIC64
        select HAVE_UID16
+       select LOCK_MM_AND_FIND_VMA
        select OLD_SIGACTION
        select ZONE_DMA
 

diff --git a/arch/sparc/mm/fault_32.c b/arch/sparc/mm/fault_32.c
index 179295b14664a55d889844790f0048c8b29ef553..a3ccc0267bc20515fcf42437430f0e410c6c2b0f 100644 (file)
--- a/arch/sparc/mm/fault_32.c
+++ b/arch/sparc/mm/fault_32.c
@@ -143,28 +143,19 @@ asmlinkage void do_sparc_fault(struct pt_regs *regs, int text_fault, int write,
        if (pagefault_disabled() || !mm)
                goto no_context;
 
+       if (!from_user && address >= PAGE_OFFSET)
+               goto no_context;
+
        perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, address);
 
 retry:
-       mmap_read_lock(mm);
-
-       if (!from_user && address >= PAGE_OFFSET)
-               goto bad_area;
-
-       vma = find_vma(mm, address);
+       vma = lock_mm_and_find_vma(mm, address, regs);
        if (!vma)
-               goto bad_area;
-       if (vma->vm_start <= address)
-               goto good_area;
-       if (!(vma->vm_flags & VM_GROWSDOWN))
-               goto bad_area;
-       if (expand_stack(vma, address))
-               goto bad_area;
+               goto bad_area_nosemaphore;
        /*
         * Ok, we have a good vm_area for this memory access, so
         * we can handle it..
         */
-good_area:
        code = SEGV_ACCERR;
        if (write) {
                if (!(vma->vm_flags & VM_WRITE))
@@ -321,17 +312,9 @@ static void force_user_fault(unsigned long address, int write)
 
        code = SEGV_MAPERR;
 
-       mmap_read_lock(mm);
-       vma = find_vma(mm, address);
+       vma = lock_mm_and_find_vma(mm, address, regs);
        if (!vma)
-               goto bad_area;
-       if (vma->vm_start <= address)
-               goto good_area;
-       if (!(vma->vm_flags & VM_GROWSDOWN))
-               goto bad_area;
-       if (expand_stack(vma, address))
-               goto bad_area;
-good_area:
+               goto bad_area_nosemaphore;
        code = SEGV_ACCERR;
        if (write) {
                if (!(vma->vm_flags & VM_WRITE))
@@ -350,6 +333,7 @@ good_area:
        return;
 bad_area:
        mmap_read_unlock(mm);
+bad_area_nosemaphore:
        __do_fault_siginfo(code, SIGSEGV, tsk->thread.kregs, address);
        return;
 

diff --git a/arch/xtensa/Kconfig b/arch/xtensa/Kconfig
index 3c6e5471f025b91c51119af68b0bb4389329f061..2d0d6440b9796ee1c6c6e7ba64d3e7f01d44aa12 100644 (file)
--- a/arch/xtensa/Kconfig
+++ b/arch/xtensa/Kconfig
@@ -49,6 +49,7 @@ config XTENSA
        select HAVE_SYSCALL_TRACEPOINTS
        select HAVE_VIRT_CPU_ACCOUNTING_GEN
        select IRQ_DOMAIN
+       select LOCK_MM_AND_FIND_VMA
        select MODULES_USE_ELF_RELA
        select PERF_USE_VMALLOC
        select TRACE_IRQFLAGS_SUPPORT

diff --git a/arch/xtensa/mm/fault.c b/arch/xtensa/mm/fault.c
index faf7cf35a0ee3d244f60332ad967da9e6d500142..d1eb8d6c5b826702b87e289b5737310cb9695995 100644 (file)
--- a/arch/xtensa/mm/fault.c
+++ b/arch/xtensa/mm/fault.c
@@ -130,23 +130,14 @@ void do_page_fault(struct pt_regs *regs)
        perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, address);
 
 retry:
-       mmap_read_lock(mm);
-       vma = find_vma(mm, address);
-
+       vma = lock_mm_and_find_vma(mm, address, regs);
        if (!vma)
-               goto bad_area;
-       if (vma->vm_start <= address)
-               goto good_area;
-       if (!(vma->vm_flags & VM_GROWSDOWN))
-               goto bad_area;
-       if (expand_stack(vma, address))
-               goto bad_area;
+               goto bad_area_nosemaphore;
 
        /* Ok, we have a good vm_area for this memory access, so
         * we can handle it..
         */
 
-good_area:
        code = SEGV_ACCERR;
 
        if (is_write) {
@@ -205,6 +196,7 @@ good_area:
         */
 bad_area:
        mmap_read_unlock(mm);
+bad_area_nosemaphore:
        if (user_mode(regs)) {
                force_sig_fault(SIGSEGV, code, (void *) address);
                return;