From: Ben Hutchings ben@decadent.org.uk
commit 7267ef7b0b77f4ed23b7b3c87d8eca7bd9c2d007 upstream.
Signed-off-by: Ben Hutchings ben@decadent.org.uk Signed-off-by: Linus Torvalds torvalds@linux-foundation.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- arch/riscv/Kconfig | 1 + arch/riscv/mm/fault.c | 31 +++++++++++++------------------ 2 files changed, 14 insertions(+), 18 deletions(-)
--- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -119,6 +119,7 @@ config RISCV select HAVE_SYSCALL_TRACEPOINTS select IRQ_DOMAIN select IRQ_FORCED_THREADING + select LOCK_MM_AND_FIND_VMA select MODULES_USE_ELF_RELA if MODULES select MODULE_SECTIONS if MODULES select OF --- a/arch/riscv/mm/fault.c +++ b/arch/riscv/mm/fault.c @@ -83,13 +83,13 @@ static inline void mm_fault_error(struct 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, 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); @@ -99,6 +99,15 @@ static inline void bad_area(struct pt_re no_context(regs, addr); }
+static inline void +bad_area(struct pt_regs *regs, struct mm_struct *mm, int code, + unsigned long addr) +{ + mmap_read_unlock(mm); + + bad_area_nosemaphore(regs, code, addr); +} + static inline void vmalloc_fault(struct pt_regs *regs, int code, unsigned long addr) { pgd_t *pgd, *pgd_k; @@ -286,23 +295,10 @@ asmlinkage void do_page_fault(struct pt_ else if (cause == EXC_INST_PAGE_FAULT) flags |= FAULT_FLAG_INSTRUCTION; retry: - mmap_read_lock(mm); - vma = find_vma(mm, addr); + vma = lock_mm_and_find_vma(mm, addr, regs); if (unlikely(!vma)) { tsk->thread.bad_cause = cause; - bad_area(regs, mm, code, addr); - return; - } - if (likely(vma->vm_start <= addr)) - goto good_area; - if (unlikely(!(vma->vm_flags & VM_GROWSDOWN))) { - tsk->thread.bad_cause = cause; - bad_area(regs, mm, code, addr); - return; - } - if (unlikely(expand_stack(vma, addr))) { - tsk->thread.bad_cause = cause; - bad_area(regs, mm, code, addr); + bad_area_nosemaphore(regs, code, addr); return; }
@@ -310,7 +306,6 @@ 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(cause, vma))) {