commit 1c811d403afd ("x86/sev: Fix position dependent variable references in startup code") introduced RIP_REL_REF() to force RIP- relative accesses to global variables, as needed to prevent crashes during early SEV/SME startup code. For completeness, RIP_REL_REF() should be used with additional variables during sme_enable() [0]. Access these vars with RIP_REL_REF() to prevent problem reoccurence.
[0] https://lore.kernel.org/all/CAMj1kXHnA0fJu6zh634=fbJswp59kSRAbhW+ubDGj1+NYwZ...
Fixes: 1c811d403afd ("x86/sev: Fix position dependent variable references in startup code") Signed-off-by: Kevin Loughlin kevinloughlin@google.com Reviewed-by: Ard Biesheuvel ardb@kernel.org Reviewed-by: Tom Lendacky thomas.lendacky@amd.com ---
v1 -> v2: Fix typo in commit message, add Ard's and Tom's "Reviewed-by"
arch/x86/mm/mem_encrypt_identity.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/arch/x86/mm/mem_encrypt_identity.c b/arch/x86/mm/mem_encrypt_identity.c index e6c7686f443a..9fce5b87b8c5 100644 --- a/arch/x86/mm/mem_encrypt_identity.c +++ b/arch/x86/mm/mem_encrypt_identity.c @@ -565,7 +565,7 @@ void __head sme_enable(struct boot_params *bp) }
RIP_REL_REF(sme_me_mask) = me_mask; - physical_mask &= ~me_mask; - cc_vendor = CC_VENDOR_AMD; + RIP_REL_REF(physical_mask) &= ~me_mask; + RIP_REL_REF(cc_vendor) = CC_VENDOR_AMD; cc_set_mask(me_mask); }