Hi Aurelien, On 02/08/14 22:35, Aurelien Jarno wrote: > On Thu, Jul 31, 2014 at 10:33:55AM -0700, David Daney wrote: >> diff --git a/arch/mips/mm/tlbex.c b/arch/mips/mm/tlbex.c >> index f99ec587..341add1 100644 >> --- a/arch/mips/mm/tlbex.c >> +++ b/arch/mips/mm/tlbex.c >> @@ -1299,6 +1299,8 @@ static void build_r4000_tlb_refill_handler(void) >> } >> #ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT >> uasm_l_tlb_huge_update(&l, p); >> + if (!use_bbit_insns()) >> + UASM_i_LW(&p, K0, 0, K1); >> build_huge_update_entries(&p, htlb_info.huge_pte, K1); >> build_huge_tlb_write_entry(&p, &l, &r, K0, tlb_random, >> htlb_info.restore_scratch); > > This patch fixes the issue, thanks. That said it doesn't look fully > correct. The test should be done the same way as for > build_fast_tlb_refill_handler. For example the fast handler is not > called on a 32-bit machine with bbit instructions, so it would need > to reload K0. In the non fast case build_is_huge_pte() will still use bbit1 if available after restoring K0, and I don't think the bbit1 would clobber K0 when the branch is taken, so I think the test for !use_bbit_insns() is correct. Cheers James
