From 47311cca31e685fa7bfe19bb8cef17d2d3d7fff9 Mon Sep 17 00:00:00 2001 From: Yury Khrustalev Date: Wed, 20 Nov 2024 11:20:33 +0000 Subject: [PATCH] manual: Add description of AArch64-specific pkey flags Describe AArch64 specific flags PKEY_DISABLE_READ and PKEY_DISABLE_EXECUTE that are available on AArch64 systems with enabled Stage 1 permission overlays feature introduced in Armv8.9 / 9.4 (FEAT_S1POE). Reviewed-by: Adhemerval Zanella --- manual/memory.texi | 16 +++++++++++++++- 1 file changed, 15 insertions(+), 1 deletion(-) diff --git a/manual/memory.texi b/manual/memory.texi index 324c1209be..dc4621e2c5 100644 --- a/manual/memory.texi +++ b/manual/memory.texi @@ -3261,6 +3261,12 @@ the page protection flags are applied. Otherwise, @var{access_restrictions} is a combination of the following flags: @vtable @code +@item PKEY_DISABLE_READ +@standards{Linux, sys/mman.h} +Subsequent attempts to read from memory with the specified protection +key will fault. At present only AArch64 platforms with enabled Stage 1 +permission overlays feature support this type of restriction. + @item PKEY_DISABLE_WRITE @standards{Linux, sys/mman.h} Subsequent attempts to write to memory with the specified protection @@ -3269,7 +3275,15 @@ key will fault. @item PKEY_DISABLE_ACCESS @standards{Linux, sys/mman.h} Subsequent attempts to write to or read from memory with the specified -protection key will fault. +protection key will fault. On AArch64 platforms with enabled Stage 1 +permission overlays feature this restriction value has the same effect +as combination of @code{PKEY_DISABLE_READ} and @code{PKEY_DISABLE_WRITE}. + +@item PKEY_DISABLE_EXECUTE +@standards{Linux, sys/mman.h} +Subsequent attempts to execute from memory with the specified protection +key will fault. At present only AArch64 platforms with enabled Stage 1 +permission overlays feature support this type of restriction. @end vtable Operations not specified as flags are not restricted. In particular,