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Diffstat (limited to 'arch/powerpc/mm/fault.c')
-rw-r--r--arch/powerpc/mm/fault.c53
1 files changed, 45 insertions, 8 deletions
diff --git a/arch/powerpc/mm/fault.c b/arch/powerpc/mm/fault.c
index 6e1e39035380..866446cf2d9a 100644
--- a/arch/powerpc/mm/fault.c
+++ b/arch/powerpc/mm/fault.c
@@ -107,7 +107,8 @@ static bool store_updates_sp(struct pt_regs *regs)
*/
static int
-__bad_area_nosemaphore(struct pt_regs *regs, unsigned long address, int si_code)
+__bad_area_nosemaphore(struct pt_regs *regs, unsigned long address, int si_code,
+ int pkey)
{
/*
* If we are in kernel mode, bail out with a SEGV, this will
@@ -117,17 +118,18 @@ __bad_area_nosemaphore(struct pt_regs *regs, unsigned long address, int si_code)
if (!user_mode(regs))
return SIGSEGV;
- _exception(SIGSEGV, regs, si_code, address);
+ _exception_pkey(SIGSEGV, regs, si_code, address, pkey);
return 0;
}
static noinline int bad_area_nosemaphore(struct pt_regs *regs, unsigned long address)
{
- return __bad_area_nosemaphore(regs, address, SEGV_MAPERR);
+ return __bad_area_nosemaphore(regs, address, SEGV_MAPERR, 0);
}
-static int __bad_area(struct pt_regs *regs, unsigned long address, int si_code)
+static int __bad_area(struct pt_regs *regs, unsigned long address, int si_code,
+ int pkey)
{
struct mm_struct *mm = current->mm;
@@ -137,17 +139,23 @@ static int __bad_area(struct pt_regs *regs, unsigned long address, int si_code)
*/
up_read(&mm->mmap_sem);
- return __bad_area_nosemaphore(regs, address, si_code);
+ return __bad_area_nosemaphore(regs, address, si_code, pkey);
}
static noinline int bad_area(struct pt_regs *regs, unsigned long address)
{
- return __bad_area(regs, address, SEGV_MAPERR);
+ return __bad_area(regs, address, SEGV_MAPERR, 0);
+}
+
+static int bad_key_fault_exception(struct pt_regs *regs, unsigned long address,
+ int pkey)
+{
+ return __bad_area_nosemaphore(regs, address, SEGV_PKUERR, pkey);
}
static noinline int bad_access(struct pt_regs *regs, unsigned long address)
{
- return __bad_area(regs, address, SEGV_ACCERR);
+ return __bad_area(regs, address, SEGV_ACCERR, 0);
}
static int do_sigbus(struct pt_regs *regs, unsigned long address,
@@ -432,6 +440,10 @@ static int __do_page_fault(struct pt_regs *regs, unsigned long address,
perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, address);
+ if (error_code & DSISR_KEYFAULT)
+ return bad_key_fault_exception(regs, address,
+ get_mm_addr_key(mm, address));
+
/*
* We want to do this outside mmap_sem, because reading code around nip
* can result in fault, which will cause a deadlock when called with
@@ -503,6 +515,31 @@ good_area:
* the fault.
*/
fault = handle_mm_fault(vma, address, flags);
+
+#ifdef CONFIG_PPC_MEM_KEYS
+ /*
+ * if the HPTE is not hashed, hardware will not detect
+ * a key fault. Lets check if we failed because of a
+ * software detected key fault.
+ */
+ if (unlikely(fault & VM_FAULT_SIGSEGV) &&
+ !arch_vma_access_permitted(vma, flags & FAULT_FLAG_WRITE,
+ is_exec, 0)) {
+ /*
+ * The PGD-PDT...PMD-PTE tree may not have been fully setup.
+ * Hence we cannot walk the tree to locate the PTE, to locate
+ * the key. Hence let's use vma_pkey() to get the key; instead
+ * of get_mm_addr_key().
+ */
+ int pkey = vma_pkey(vma);
+
+ if (likely(pkey)) {
+ up_read(&mm->mmap_sem);
+ return bad_key_fault_exception(regs, address, pkey);
+ }
+ }
+#endif /* CONFIG_PPC_MEM_KEYS */
+
major |= fault & VM_FAULT_MAJOR;
/*
@@ -576,7 +613,7 @@ void bad_page_fault(struct pt_regs *regs, unsigned long address, int sig)
/* kernel has accessed a bad area */
- switch (regs->trap) {
+ switch (TRAP(regs)) {
case 0x300:
case 0x380:
printk(KERN_ALERT "Unable to handle kernel paging request for "