diff options
Diffstat (limited to 'arch/um/kernel/trap_kern.c')
| -rw-r--r-- | arch/um/kernel/trap_kern.c | 21 |
1 files changed, 20 insertions, 1 deletions
diff --git a/arch/um/kernel/trap_kern.c b/arch/um/kernel/trap_kern.c index 87cc6fd76ced..95c8f8733baf 100644 --- a/arch/um/kernel/trap_kern.c +++ b/arch/um/kernel/trap_kern.c @@ -18,6 +18,7 @@ #include "asm/a.out.h" #include "asm/current.h" #include "asm/irq.h" +#include "sysdep/sigcontext.h" #include "user_util.h" #include "kern_util.h" #include "kern.h" @@ -25,6 +26,9 @@ #include "mconsole_kern.h" #include "mem.h" #include "mem_kern.h" +#ifdef CONFIG_MODE_SKAS +#include "skas.h" +#endif /* Note this is constrained to return 0, -EFAULT, -EACCESS, -ENOMEM by segv(). */ int handle_page_fault(unsigned long address, unsigned long ip, @@ -39,6 +43,12 @@ int handle_page_fault(unsigned long address, unsigned long ip, int err = -EFAULT; *code_out = SEGV_MAPERR; + + /* If the fault was during atomic operation, don't take the fault, just + * fail. */ + if (in_atomic()) + goto out_nosemaphore; + down_read(&mm->mmap_sem); vma = find_vma(mm, address); if(!vma) @@ -89,6 +99,7 @@ survive: flush_tlb_page(vma, address); out: up_read(&mm->mmap_sem); +out_nosemaphore: return(err); /* @@ -125,7 +136,15 @@ unsigned long segv(struct faultinfo fi, unsigned long ip, int is_user, void *sc) } else if(current->mm == NULL) panic("Segfault with no mm"); - err = handle_page_fault(address, ip, is_write, is_user, &si.si_code); + + if (SEGV_IS_FIXABLE(&fi) || SEGV_MAYBE_FIXABLE(&fi)) + err = handle_page_fault(address, ip, is_write, is_user, &si.si_code); + else { + err = -EFAULT; + /* A thread accessed NULL, we get a fault, but CR2 is invalid. + * This code is used in __do_copy_from_user() of TT mode. */ + address = 0; + } catcher = current->thread.fault_catcher; if(!err) |