From 02ba3afe4c5bcf847770e0acab1ffa40b5350f9f Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Mon, 23 Jun 2014 15:16:36 -0400 Subject: [PATCH] 3.15-stable patches added patches: mips-kvm-allocate-at-least-16kb-for-exception-handlers.patch --- ...at-least-16kb-for-exception-handlers.patch | 50 +++++++++++++++++++ queue-3.15/series | 1 + 2 files changed, 51 insertions(+) create mode 100644 queue-3.15/mips-kvm-allocate-at-least-16kb-for-exception-handlers.patch diff --git a/queue-3.15/mips-kvm-allocate-at-least-16kb-for-exception-handlers.patch b/queue-3.15/mips-kvm-allocate-at-least-16kb-for-exception-handlers.patch new file mode 100644 index 00000000000..5d5f860cc99 --- /dev/null +++ b/queue-3.15/mips-kvm-allocate-at-least-16kb-for-exception-handlers.patch @@ -0,0 +1,50 @@ +From 7006e2dfda9adfa40251093604db76d7e44263b3 Mon Sep 17 00:00:00 2001 +From: James Hogan +Date: Thu, 29 May 2014 10:16:23 +0100 +Subject: MIPS: KVM: Allocate at least 16KB for exception handlers + +From: James Hogan + +commit 7006e2dfda9adfa40251093604db76d7e44263b3 upstream. + +Each MIPS KVM guest has its own copy of the KVM exception vector. This +contains the TLB refill exception handler at offset 0x000, the general +exception handler at offset 0x180, and interrupt exception handlers at +offset 0x200 in case Cause_IV=1. A common handler is copied to offset +0x2000 and offset 0x3000 is used for temporarily storing k1 during entry +from guest. + +However the amount of memory allocated for this purpose is calculated as +0x200 rounded up to the next page boundary, which is insufficient if 4KB +pages are in use. This can lead to the common handler at offset 0x2000 +being overwritten and infinitely recursive exceptions on the next exit +from the guest. + +Increase the minimum size from 0x200 to 0x4000 to cover the full use of +the page. + +Signed-off-by: James Hogan +Cc: Paolo Bonzini +Cc: Gleb Natapov +Cc: kvm@vger.kernel.org +Cc: Ralf Baechle +Cc: linux-mips@linux-mips.org +Cc: Sanjay Lal +Signed-off-by: Paolo Bonzini +Signed-off-by: Greg Kroah-Hartman + +--- + arch/mips/kvm/kvm_mips.c | 2 +- + 1 file changed, 1 insertion(+), 1 deletion(-) + +--- a/arch/mips/kvm/kvm_mips.c ++++ b/arch/mips/kvm/kvm_mips.c +@@ -304,7 +304,7 @@ struct kvm_vcpu *kvm_arch_vcpu_create(st + if (cpu_has_veic || cpu_has_vint) { + size = 0x200 + VECTORSPACING * 64; + } else { +- size = 0x200; ++ size = 0x4000; + } + + /* Save Linux EBASE */ diff --git a/queue-3.15/series b/queue-3.15/series index 30ffc37b3b2..960f30e8713 100644 --- a/queue-3.15/series +++ b/queue-3.15/series @@ -22,3 +22,4 @@ udp-ipv4-do-not-waste-time-in.patch arm-at91-fix-at91_sysirq_mask_rtc-for-sam9x5-socs.patch kvm-lapic-sync-highest-isr-to-hardware-apic-on-eoi.patch kvm-s390-drop-pending-interrupts-on-guest-exit.patch +mips-kvm-allocate-at-least-16kb-for-exception-handlers.patch -- 2.47.3