From 1f404058e2911afe08417ef82f17aba6adccfc63 Mon Sep 17 00:00:00 2001 From: "Aneesh Kumar K.V" Date: Thu, 9 Jul 2020 08:59:28 +0530 Subject: [PATCH] powerpc/book3s64/pkeys: Explain key 1 reservation details This explains the details w.r.t key 1. Signed-off-by: Aneesh Kumar K.V Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20200709032946.881753-6-aneesh.kumar@linux.ibm.com --- arch/powerpc/mm/book3s64/pkeys.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/arch/powerpc/mm/book3s64/pkeys.c b/arch/powerpc/mm/book3s64/pkeys.c index 82ace6a..ee27f18 100644 --- a/arch/powerpc/mm/book3s64/pkeys.c +++ b/arch/powerpc/mm/book3s64/pkeys.c @@ -128,7 +128,10 @@ static int pkey_initialize(void) #else os_reserved = 0; #endif - /* Bits are in LE format. */ + /* + * key 1 is recommended not to be used. PowerISA(3.0) page 1015, + * programming note. + */ reserved_allocation_mask = (0x1 << 1) | (0x1 << execute_only_key); /* register mask is in BE format */ -- 2.7.4