[xen staging-4.12] x86/idle: Extend ISR/C6 erratum workaround to Haswell

[patchbot@xxxxxxx]

commit 1f581f966a789c29d05dd7d9d58d98dba06c01c9
Author:     Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
AuthorDate: Wed Jun 24 17:03:30 2020 +0200
Commit:     Jan Beulich <jbeulich@xxxxxxxx>
CommitDate: Wed Jun 24 17:03:30 2020 +0200

    x86/idle: Extend ISR/C6 erratum workaround to Haswell
    
    This bug was first discovered against Haswell.  It is definitely affected.
    
    (The XenServer ticket for this bug was opened on 2013-05-30 which is coming 
up
    on 7 years old, and predates Broadwell).
    
    Signed-off-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
    Acked-by: Jan Beulich <jbeulich@xxxxxxxx>
    master commit: b72d8870b5f68f06b083e6bfdb28f081bcb6ab3b
    master date: 2020-05-22 20:04:23 +0100
---
 xen/arch/x86/acpi/cpu_idle.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/xen/arch/x86/acpi/cpu_idle.c b/xen/arch/x86/acpi/cpu_idle.c
index e879f8dfe9..4ff8693ae6 100644
--- a/xen/arch/x86/acpi/cpu_idle.c
+++ b/xen/arch/x86/acpi/cpu_idle.c
@@ -550,8 +550,16 @@ bool errata_c6_workaround(void)
          * registers), the processor may dispatch the second interrupt (from
          * the IRR bit) before the first interrupt has completed and written to
          * the EOI register, causing the first interrupt to never complete.
+         *
+         * Note: Haswell hasn't had errata issued, but this issue was first
+         * discovered on Haswell hardware, and is affected.
          */
         static const struct x86_cpu_id isr_errata[] = {
+            /* Haswell */
+            INTEL_FAM6_MODEL(0x3c),
+            INTEL_FAM6_MODEL(0x3f),
+            INTEL_FAM6_MODEL(0x45),
+            INTEL_FAM6_MODEL(0x46),
             /* Broadwell */
             INTEL_FAM6_MODEL(0x47),
             INTEL_FAM6_MODEL(0x3d),
--
generated by git-patchbot for /home/xen/git/xen.git#staging-4.12