CVSROOT: /cvs
Module name: src
Changes by: gkoeh...@cvs.openbsd.org 2022/02/07 16:20:10
Modified files:
sys/arch/powerpc/powerpc: pmap.c
Log message:
Allow writes to rw pages in pte_spill_v
In the powerpc pmap, hash collisions can spill page table entries.
Page faults can use pte_spill_v to reinsert a spilled pte. If the
fault is a write (DSISR_STORE), then pte_spill_v tries to check for a
read-only page. The existing check (pte_lo & PTE_RO_64) also matched
rw pages, because PTE_RO_64 is 3 and PTE_RW_64 is 2. This caused
pte_spill_v to deny writes to rw pages. Then uvm_fault might allow
the write; but uvm_fault can't handle some pages in the kernel. Such
faults caused, "panic: uvm_fault: fault on non-pageable map", or
"panic: trap type 300".
Change it to ((pte_lo & PTE_PP_64) == PTE_RO_64). This seems to fix
one reason why bsd.mp on a macppc dual G5 might panic.
ok kettenis@ miod@
