Re: [Xen-devel] [PATCH v5 15/28] xsplice: Add .xsplice.hooks functions and test-case

["Jan Beulich" <JBeulich@xxxxxxxx>]

>>> On 11.04.16 at 10:23, <ross.lagerwall@xxxxxxxxxx> wrote:
> Some examples:
> XSA-80: In addition to patching the code, a hook function is needed to 
> set iommu_dont_flush_iotlb back to 0.

I don't think this is an issue that can be reasonably life patched:
Doing so would likely lead to the false impression that everything
is fine after the patching, which it isn't as you don't know what
other flushing didn't happen as needed, and hence what else is
in a broken state at the point of patching.

> XSA-82: The original patch applies to an __init function. Instead, use a 
> hook function to update the MSR.

__devinit == <nothing> (i.e. != __init)

The right way to deal with MSR value changes post boot imo is
to run a utility from Dom0 user mode which fiddles with the MSR
on all CPUs. No need for a patch to also deal with machine state.

Jan


_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
http://lists.xen.org/xen-devel