Messages in this thread | | | Subject | Re: [PATCH 20/24] objtool: Another static block fail | From | David Woodhouse <> | Date | Wed, 31 Jan 2018 10:07:06 +0000 |
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On Wed, 2018-01-31 at 11:01 +0100, Peter Zijlstra wrote: > On Tue, Jan 30, 2018 at 09:12:21PM -0600, Josh Poimboeuf wrote: > > > > Or, maybe we should just forget the whole thing and just stick with the > > dynamic IBRS checks with lfence. Yes, it's less ideal for the kernel, > > but adding these acrobatics to objtool also has a cost. > > For now, IBRS seems off the table entirely. But no, I really don't want > to have to unconditionally eat the LFENCE cost in all those sites.
There's also alternatives. And without the IBRS-on-kernel-entry bits there aren't that many call sites that really need this anyway and don't have *other* conditionals that really are runtime-only (like dumpable etc.).[unhandled content-type:application/x-pkcs7-signature]
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