Commit a9015502 authored Oct 26, 2021 by Peter Zijlstra Committed by Greg Kroah-Hartman Mar 11, 2022

x86,bugs: Unconditionally allow spectre_v2=retpoline,amd



commit f8a66d608a3e471e1202778c2a36cbdc96bae73b upstream.

Currently Linux prevents usage of retpoline,amd on !AMD hardware, this
is unfriendly and gets in the way of testing. Remove this restriction.

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/20211026120310.487348118@infradead.org


[fllinden@amazon.com: backported to 4.19 (no Hygon in 4.19)]
Signed-off-by: Frank van der Linden <fllinden@amazon.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent 71d79539

arch/x86/kernel/cpu/bugs.c

+0 −6

Original line number	Diff line number	Diff line
		@@ -838,12 +838,6 @@ static enum spectre_v2_mitigation_cmd __init spectre_v2_parse_cmdline(void)
		return SPECTRE_V2_CMD_AUTO;
		}

		if (cmd == SPECTRE_V2_CMD_RETPOLINE_AMD &&
		boot_cpu_data.x86_vendor != X86_VENDOR_AMD) {
		pr_err("retpoline,amd selected but CPU is not AMD. Switching to AUTO select\n");
		return SPECTRE_V2_CMD_AUTO;
		}

		spec_v2_print_cond(mitigation_options[i].option,
		mitigation_options[i].secure);
		return cmd;