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| author | jhb <jhb@FreeBSD.org> | 2010-08-02 17:01:23 +0000 |
|---|---|---|
| committer | jhb <jhb@FreeBSD.org> | 2010-08-02 17:01:23 +0000 |
| commit | c6eb2c5ec7d96a646b6c4835ff209a178481f669 (patch) | |
| tree | 5d75737cf66c58d8a7638e8350c82d7278adc1dc /sys/amd64 | |
| parent | ec28b7bf63c9ab049a292f7f3895fe1ffa976f88 (diff) | |
| download | FreeBSD-src-c6eb2c5ec7d96a646b6c4835ff209a178481f669.zip FreeBSD-src-c6eb2c5ec7d96a646b6c4835ff209a178481f669.tar.gz | |
Tweak the logic to disable CLFLUSH in virtual environments to work around
problems with flushing the local APIC register range so that it checks
vm_guest directly.
Reviewed by: kib, alc
MFC after: 2 weeks
Diffstat (limited to 'sys/amd64')
| -rw-r--r-- | sys/amd64/amd64/initcpu.c | 12 |
1 files changed, 6 insertions, 6 deletions
diff --git a/sys/amd64/amd64/initcpu.c b/sys/amd64/amd64/initcpu.c index c97ad3d..923b28c 100644 --- a/sys/amd64/amd64/initcpu.c +++ b/sys/amd64/amd64/initcpu.c @@ -177,17 +177,17 @@ initializecpucache() if ((cpu_feature & CPUID_CLFSH) != 0) cpu_clflush_line_size = ((cpu_procinfo >> 8) & 0xff) * 8; /* - * XXXKIB: (temporary) hack to work around traps generated when - * CLFLUSHing APIC registers window. + * XXXKIB: (temporary) hack to work around traps generated + * when CLFLUSHing APIC register window under virtualization + * environments. These environments tend to disable the + * CPUID_SS feature even though the native CPU supports it. */ TUNABLE_INT_FETCH("hw.clflush_disable", &hw_clflush_disable); - if (cpu_vendor_id == CPU_VENDOR_INTEL && !(cpu_feature & CPUID_SS) && - hw_clflush_disable == -1) + if (vm_guest != VM_GUEST_NO && hw_clflush_disable == -1) cpu_feature &= ~CPUID_CLFSH; /* * Allow to disable CLFLUSH feature manually by - * hw.clflush_disable tunable. This may help Xen guest on some AMD - * CPUs. + * hw.clflush_disable tunable. */ if (hw_clflush_disable == 1) cpu_feature &= ~CPUID_CLFSH; |
