riscv equivalent of 26178ec11ef3 "x86: mm: consolidate VM_FAULT_RETRY handling"
If e.g. get_user() triggers a page fault and a fatal signal is caught, we might
end up with handle_mm_fault() returning VM_FAULT_RETRY and not doing anything
to page tables. In such case we must *not* return to the faulting insn -
that would repeat the entire thing without making any progress; what we need
instead is to treat that as failed (user) memory access.
Signed-off-by: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
---
arch/riscv/mm/fault.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/arch/riscv/mm/fault.c b/arch/riscv/mm/fault.c
index d86f7cebd4a7..c91d85349d39 100644
--- a/arch/riscv/mm/fault.c
+++ b/arch/riscv/mm/fault.c
@@ -324,8 +324,11 @@ asmlinkage void do_page_fault(struct pt_regs *regs)
* signal first. We do not need to release the mmap_lock because it
* would already be released in __lock_page_or_retry in mm/filemap.c.
*/
- if (fault_signal_pending(fault, regs))
+ if (fault_signal_pending(fault, regs)) {
+ if (!user_mode(regs))
+ no_context(regs, addr);
return;
+ }
/* The fault is fully completed (including releasing mmap lock) */
if (fault & VM_FAULT_COMPLETED)
--
2.30.2
