From: Aneesh Kumar K.V Date: Sun, 26 Jul 2020 13:25:17 +0000 (+0530) Subject: powerpc/book3s64/pkey: Disable pkey on POWER6 and before X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=269e829f48a0d0d27667abe25ca5c9e5b6ab08e2;p=linux.git powerpc/book3s64/pkey: Disable pkey on POWER6 and before POWER6 only supports AMR update via privileged mode (MSR[PR] = 0, SPRN_AMR=29) The PR=1 (userspace) alias for that SPR (SPRN_AMR=13) was only supported from POWER7. Since we don't allow userspace modifying of AMR value we should disable pkey support on P6 and before. The hypervisor will still report pkey support via "ibm,processor-storage-keys". Hence also check for P7 CPU_FTR bit to decide on pkey support. Fixes: f491fe3fb41e ("powerpc/book3s64/pkeys: Simplify the key initialization") Reported-by: Michael Ellerman Signed-off-by: Aneesh Kumar K.V Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20200726132517.399076-1-aneesh.kumar@linux.ibm.com --- diff --git a/arch/powerpc/mm/book3s64/pkeys.c b/arch/powerpc/mm/book3s64/pkeys.c index 792b36aa9619e..69a6b87f2bb4e 100644 --- a/arch/powerpc/mm/book3s64/pkeys.c +++ b/arch/powerpc/mm/book3s64/pkeys.c @@ -73,6 +73,12 @@ static int scan_pkey_feature(void) if (early_radix_enabled()) return 0; + /* + * Only P7 and above supports SPRN_AMR update with MSR[PR] = 1 + */ + if (!early_cpu_has_feature(CPU_FTR_ARCH_206)) + return 0; + ret = of_scan_flat_dt(dt_scan_storage_keys, &pkeys_total); if (ret == 0) { /*