xen/51d5334e-x86-mm-Ensure-useful-progress-in-alloc_l2_table.patch
Charles Arnold 73291eb01a - bnc#836239 - SLES 11 SP3 Xen security patch does not
automatically update UEFI boot binary
  xen.spec

- Upstream patches from Jan
  51d5334e-x86-mm-Ensure-useful-progress-in-alloc_l2_table.patch
  51dd155c-adjust-x86-EFI-build.patch
  51e63d80-x86-cpuidle-Change-logging-for-unknown-APIC-IDs.patch
  51e6540d-x86-don-t-use-destroy_xen_mappings-for-vunmap.patch
  51e7963f-x86-time-Update-wallclock-in-shared-info-when-altering-domain-time-offset.patch
  51ffd577-fix-off-by-one-mistakes-in-vm_alloc.patch
  51ffd5fd-x86-refine-FPU-selector-handling-code-for-XSAVEOPT.patch
  520114bb-Nested-VMX-Flush-TLBs-and-Caches-if-paging-mode-changed.patch
  520a5504-VMX-add-boot-parameter-to-enable-disable-APIC-v-dynamically.patch
  520a24f6-x86-AMD-Fix-nested-svm-crash-due-to-assertion-in-__virt_to_maddr.patch
  520a2570-x86-AMD-Inject-GP-instead-of-UD-when-unable-to-map-vmcb.patch
  520b4b60-VT-d-protect-against-bogus-information-coming-from-BIOS.patch
  520b4bda-x86-MTRR-fix-range-check-in-mtrr_add_page.patch
  520cb8b6-x86-time-fix-check-for-negative-time-in-__update_vcpu_system_time.patch
  520d417d-xen-Add-stdbool.h-workaround-for-BSD.patch

OBS-URL: https://build.opensuse.org/package/show/Virtualization/xen?expand=0&rev=266
2013-08-29 18:19:23 +00:00

31 lines
1.2 KiB
Diff

# Commit d3a55d7d9bb518efe08143d050deff9f4ee80ec1
# Date 2013-07-04 10:33:18 +0200
# Author Andrew Cooper <andrew.cooper3@citrix.com>
# Committer Jan Beulich <jbeulich@suse.com>
x86/mm: Ensure useful progress in alloc_l2_table()
While debugging the issue which turned out to be XSA-58, a printk in this loop
showed that it was quite easy to never make useful progress, because of
consistently failing the preemption check.
One single l2 entry is a reasonable amount of work to do, even if an action is
pending, and also assures forwards progress across repeat continuations.
Tweak the continuation criteria to fail on the first iteration of the loop.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Keir Fraser <keir@xen.org>
--- a/xen/arch/x86/mm.c
+++ b/xen/arch/x86/mm.c
@@ -1278,7 +1278,8 @@ static int alloc_l2_table(struct page_in
for ( i = page->nr_validated_ptes; i < L2_PAGETABLE_ENTRIES; i++ )
{
- if ( preemptible && i && hypercall_preempt_check() )
+ if ( preemptible && i > page->nr_validated_ptes
+ && hypercall_preempt_check() )
{
page->nr_validated_ptes = i;
rc = -EAGAIN;