Pull arm64 fixes from Will Deacon:
"The big fix here is to our vDSO sigreturn trampoline as, after a
painfully long stint of debugging, it turned out that fixing some of
our CFI directives in the merge window lit up a bunch of logic in
libgcc which has been shown to SEGV in some cases during asynchronous
pthread cancellation.
It looks like we can fix this by extending the directives to restore
most of the interrupted register state from the sigcontext, but it's
risky and hard to test so we opted to remove the CFI directives for
now and rely on the unwinder fallback path like we used to.
- Fix unwinding through vDSO sigreturn trampoline
- Fix build warnings by raising minimum LD version for PAC
- Whitelist some Kryo Cortex-A55 derivatives for Meltdown and SSB
- Fix perf register PC reporting for compat tasks
- Fix 'make clean' warning for arm64 signal selftests
- Fix ftrace when BTI is compiled in
- Avoid building the compat vDSO using GCC plugins"
* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
arm64: Add KRYO{3,4}XX silver CPU cores to SSB safelist
arm64: perf: Report the PC value in REGS_ABI_32 mode
kselftest: arm64: Remove redundant clean target
arm64: kpti: Add KRYO{3, 4}XX silver CPU cores to kpti safelist
arm64: Don't insert a BTI instruction at inner labels
arm64: vdso: Don't use gcc plugins for building vgettimeofday.c
arm64: vdso: Only pass --no-eh-frame-hdr when linker supports it
arm64: Depend on newer binutils when building PAC
arm64: compat: Remove 32-bit sigreturn code from the vDSO
arm64: compat: Always use sigpage for sigreturn trampoline
arm64: compat: Allow 32-bit vdso and sigpage to co-exist
arm64: vdso: Disable dwarf unwinding through the sigreturn trampoline