Peter Zijlstra 381fd04c97 x86/alternative: Implement .retpoline_sites support ... commit 7508500900814d14e2e085cdc4e28142721abbdf upstream. Rewrite retpoline thunk call sites to be indirect calls for spectre_v2=off. This ensures spectre_v2=off is as near to a RETPOLINE=n build as possible. This is the replacement for objtool writing alternative entries to ensure the same and achieves feature-parity with the previous approach. One noteworthy feature is that it relies on the thunks to be in machine order to compute the register index. Specifically, this does not yet address the Jcc __x86_indirect_thunk_* calls generated by clang, a future patch will add this. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Borislav Petkov <bp@suse.de> Acked-by: Josh Poimboeuf <jpoimboe@redhat.com> Tested-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/r/20211026120310.232495794@infradead.org [cascardo: small conflict fixup at arch/x86/kernel/module.c] Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com> [bwh: Backported to 5.10: - Use hex literal instead of BYTES_NOP1 - Adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2022-07-25 11:26:26 +02:00
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configs
drivers	um: chan_user: Fix winch_tramp() return value	2022-06-09 10:21:26 +02:00
include	ptrace/um: Replace PT_DTRACE with TIF_SINGLESTEP	2022-06-09 10:20:49 +02:00
kernel	x86/alternative: Implement .retpoline_sites support	2022-07-25 11:26:26 +02:00
os-Linux	um: registers: Rename function names to avoid conflicts and build problems	2022-01-27 10:54:18 +01:00
scripts
.gitignore
Kconfig	Merge branch 'work.set_fs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs	2020-10-22 09:59:21 -07:00
Kconfig.debug	um: Disable CONFIG_GCOV with MODULES	2021-05-22 11:40:53 +02:00
Makefile
Makefile-os-Linux
Makefile-skas