search for: __llvm_retpoline_push

Displaying 6 results from an estimated 6 matches for "__llvm_retpoline_push".

2018 Feb 09
0
retpoline mitigation and 6.0
On Fri, 2018-02-09 at 11:24 -0800, Reid Kleckner wrote: > I haven't read the all the emails in full detail, but it seems pretty > clear that  __x86_indirect_thunk and __llvm_retpoline_push do not do > the same things. It sounds like __llvm_retpoline_push is equivalent > to __x86_indirect_thunk except first it swaps the two words on the > top of the stack. > > I arranged it this way because the x86 call instruction puts the > intended return address on the top of th...
2018 Feb 09
3
retpoline mitigation and 6.0
...hink I found another one that looks like this: $ clang -S -O2 -m32 -mregparm=3 -mretpoline spill_across_rp.cpp -o - | grep _retpoline_push -B2 ... movl %eax, 8(%esp) # 4-byte Spill ... pushl %edi movl 8(%esp), %edi # 4-byte Reload calll __llvm_retpoline_push That's obviously broken, it doesn't account for the SP adjustment in the push. It's weird, because it's basically the opposite of the problem you're having, which looks like LLVM *is* accounting for the push and is trying to adjust its offsets accordingly. Can you send along...
2018 Feb 09
3
retpoline mitigation and 6.0
I haven't read the all the emails in full detail, but it seems pretty clear that __x86_indirect_thunk and __llvm_retpoline_push do not do the same things. It sounds like __llvm_retpoline_push is equivalent to __x86_indirect_thunk except first it swaps the two words on the top of the stack. I arranged it this way because the x86 call instruction puts the intended return address on the top of the stack, and there's no ea...
2018 Feb 19
0
retpoline mitigation and 6.0
...s: > > $ clang -S -O2 -m32 -mregparm=3 -mretpoline spill_across_rp.cpp -o - | grep > _retpoline_push -B2 > ... > movl %eax, 8(%esp) # 4-byte Spill > ... > pushl %edi > movl 8(%esp), %edi # 4-byte Reload > calll __llvm_retpoline_push > > That's obviously broken, it doesn't account for the SP adjustment in the > push. > > It's weird, because it's basically the opposite of the problem you're > having, which looks like LLVM *is* accounting for the push and is trying to > adjust its offsets...
2018 Feb 09
0
retpoline mitigation and 6.0
On Fri, 2018-02-09 at 12:54 +0000, David Woodhouse wrote: > On Fri, 2018-02-09 at 10:36 +0000, David Woodhouse wrote: > >  > > Did you get anywhere with the function attribute? Having isolated the > > next boot failure to "it goes away if I compile io_apic.c without > > retpoline", bisecting it per-function would help to further delay the > > bit where I
2018 Feb 09
2
retpoline mitigation and 6.0
On Fri, 2018-02-09 at 10:36 +0000, David Woodhouse wrote: > > Did you get anywhere with the function attribute? Having isolated the > next boot failure to "it goes away if I compile io_apic.c without > retpoline", bisecting it per-function would help to further delay the > bit where I actually have to start *thinking*... It's mp_register_ioapic(), and only when