On 02/27/2017 02:09 PM, Steven Rostedt wrote: > On Mon, 27 Feb 2017 13:41:13 -0800 > David Daney wrote: > >> On 02/27/2017 01:06 PM, Steven Rostedt wrote: >>> On Mon, 27 Feb 2017 11:59:50 -0800 >>> David Daney wrote: >>> >>>> For me the size is not the important issue, it is the alignment of the >>>> struct jump_entry entries in the table. I don't understand how your >>>> patch helps, and I cannot Acked-by unless I understand what is being >>>> done and can see that it is both correct and necessary. >>> >>> You brought up a very good point and I'm glad that I had Jason Cc all >>> the arch maintainers in one patch. >>> >>> I think jump_labels may be much more broken than we think, and Jason's >>> fix doesn't fix anything. We had this same issues with tracepoints. >>> >>> I'm looking at jump_label_init, and how we iterate over an array of >>> struct jump_entry's that was put together by the linker. The problem is >>> that jump_entry is not a power of 2 in size. >>> >> >> ELF sections may have an ENTSIZE property exactly for arrays. Since >> each jump_entry will have a unique value they cannot be merged, but we >> can tell the assembler they are an array and get them properly packed. >> Perhaps something like (untested): >> >> .pushsection __jump_table, \"awM\",@progbits,24 >> FOO >> .popsection >> > > And the linker will honor this too? See attached for mips. It seems to do the right thing. I leave it as an exercise to the reader to fix the other architectures. Consult your own binutils experts to verify that what I say is true. David Daney