[PATCH 6/6] arm64: switch to relative exception tables
From: Ard Biesheuvel <hidden>
Date: 2016-01-04 19:28:55
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On 4 January 2016 at 20:21, H. Peter Anvin [off-list ref] wrote:
On 01/04/2016 10:20 AM, Luck, Tony wrote:quoted
quoted
May I humbly ask why the [Finnish] you don't use the equivalent of the x86 _ASM_EXTABLE() macro? In fact, why don't we make that one generic, too?I'm messing with that right now (with help from Andy Lutomirski and Boris) to add different classes of exception table (so I can tag some instructions as being suitable for fixup from the machine check handler). So it might not be generic for much longer. http://marc.info/?l=linux-kernel&m=145187079504846&w=2I suspect that means we will also need to go back to arch-specific sorting for x86.
AFAICT, Tony's patches are not incompatible with mine. The fixup address is offset with a large constant, but this does not affect the sort order (since that is based on the other member), and the swap operation that adds/subtracts the delta should not care about the class bits. (I don't see any changes to sort_extable() in Tony's patch) @Tony: any comments? And do you have any objections to the ia64 patch in this series? I agree that it makes sense to define a macro to emit the extable entries in this patch, but I am not sure how that extrapolates to the other architectures, and testing those is going to be cumbersome for me, so I'd prefer to keep that a local change for arm64 for now. Thanks, Ard.