Author: jrtc27
Date: Mon Apr 6 22:29:15 2020
New Revision: 359671
URL: https://svnweb.freebsd.org/changeset/base/359671
Log:
riscv: Fix pmap_fault_fixup for L3 pages
Summary:
The parentheses being in the wrong place means that, for L3 pages,
oldpte has all bits except PTE_V cleared, and so all the subsequent
checks against oldpte will fail, causing us to bail out and not retry
the faulting instruction after an SFENCE.VMA. This causes a WITNESS +
INVARIANTS kernel to fault on the "Chisel P3" (BOOM-based) DARPA SSITH
GFE SoC in pmap_init when writing to pv_table and, being a nofault
entry, subsequently panic with:
panic: vm_fault_lookup: fault on nofault entry, addr: 0xffffffc004e00000
Reviewed by: markj
Approved by: markj
Differential Revision: https://reviews.freebsd.org/D24315
Modified:
head/sys/riscv/riscv/pmap.c
Modified: head/sys/riscv/riscv/pmap.c
==============================================================================
--- head/sys/riscv/riscv/pmap.c Mon Apr 6 22:14:50 2020 (r359670)
+++ head/sys/riscv/riscv/pmap.c Mon Apr 6 22:29:15 2020 (r359671)
@@ -2416,7 +2416,7 @@ pmap_fault_fixup(pmap_t pmap, vm_offset_t va, vm_prot_
goto done;
if ((l2e & PTE_RWX) == 0) {
pte = pmap_l2_to_l3(l2, va);
- if (pte == NULL || ((oldpte = pmap_load(pte) & PTE_V)) == 0)
+ if (pte == NULL || ((oldpte = pmap_load(pte)) & PTE_V) == 0)
goto done;
} else {
pte = l2;
_______________________________________________
svn-src-head@freebsd.org mailing list
https://lists.freebsd.org/mailman/listinfo/svn-src-head
To unsubscribe, send any mail to "svn-src-head-unsubscr...@freebsd.org"
