Commit a1152be3 authored by James Morse's avatar James Morse
Browse files

arm64: proton-pack: Expose whether the branchy loop k value 



Add a helper to expose the k value of the branchy loop. This is needed
by the BPF JIT to generate the mitigation sequence in BPF programs.

Signed-off-by: default avatarJames Morse <james.morse@arm.com>
Reviewed-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
parent e7956c92

arch/arm64/include/asm/spectre.h

+1 −0
Original line number Diff line number Diff line
@@ -97,6 +97,7 @@ enum mitigation_state arm64_get_meltdown_state(void); 


enum mitigation_state arm64_get_spectre_bhb_state(void);

bool is_spectre_bhb_affected(const struct arm64_cpu_capabilities *entry, int scope);

u8 get_spectre_bhb_loop_value(void);

bool is_spectre_bhb_fw_mitigated(void);

void spectre_bhb_enable_mitigation(const struct arm64_cpu_capabilities *__unused);

bool try_emulate_el1_ssbs(struct pt_regs *regs, u32 instr);

arch/arm64/kernel/proton-pack.c

+5 −0
Original line number Diff line number Diff line
@@ -999,6 +999,11 @@ bool is_spectre_bhb_affected(const struct arm64_cpu_capabilities *entry, 
	return true;

}



u8 get_spectre_bhb_loop_value(void)

{

	return max_bhb_k;

}



static void this_cpu_set_vectors(enum arm64_bp_harden_el1_vectors slot)

{

	const char *v = arm64_get_bp_hardening_vector(slot);