[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] Re: [Xen-devel] [PATCH 2/2] x86, amd_ucode: Safeguard against #GP
On 30/07/14 17:13, Aravind Gopalakrishnan wrote: > When HW tries to load a corrupted patch, it generates #GP > and depending on 'noreboot' parameter on grub, the system > is either stuck in a reboot loop or is hung. Use wrmsr_safe > instead of wrmsrl so that we fail to load microcode gracefully. > > Signed-off-by: Aravind Gopalakrishnan <aravind.gopalakrishnan@xxxxxxx> > Reviewed-by: Boris Ostrovsky <boris.ostrovsky@xxxxxxxxxx> Reviewed-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx> > --- > xen/arch/x86/microcode_amd.c | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) > > diff --git a/xen/arch/x86/microcode_amd.c b/xen/arch/x86/microcode_amd.c > index a2bdd20..57646c4 100644 > --- a/xen/arch/x86/microcode_amd.c > +++ b/xen/arch/x86/microcode_amd.c > @@ -193,6 +193,7 @@ static int apply_microcode(int cpu) > uint32_t rev; > struct microcode_amd *mc_amd = uci->mc.mc_amd; > struct microcode_header_amd *hdr; > + int hw_err; > > /* We should bind the task to the CPU */ > BUG_ON(raw_smp_processor_id() != cpu); > @@ -206,7 +207,7 @@ static int apply_microcode(int cpu) > > spin_lock_irqsave(µcode_update_lock, flags); > > - wrmsrl(MSR_AMD_PATCHLOADER, (unsigned long)hdr); > + hw_err = wrmsr_safe(MSR_AMD_PATCHLOADER, (unsigned long)hdr); > > /* get patch id after patching */ > rdmsrl(MSR_AMD_PATCHLEVEL, rev); > @@ -214,7 +215,7 @@ static int apply_microcode(int cpu) > spin_unlock_irqrestore(µcode_update_lock, flags); > > /* check current patch id and patch's id for match */ > - if ( rev != hdr->patch_id ) > + if ( hw_err || (rev != hdr->patch_id) ) > { > printk(KERN_ERR "microcode: CPU%d update from revision " > "%#x to %#x failed\n", cpu, rev, hdr->patch_id); _______________________________________________ Xen-devel mailing list Xen-devel@xxxxxxxxxxxxx http://lists.xen.org/xen-devel
|
Lists.xenproject.org is hosted with RackSpace, monitoring our |