From 163e3ac90b9f12b541a237ffd266c48eae5c8a2c Mon Sep 17 00:00:00 2001 From: Timon Kruiper Date: Fri, 27 Jan 2023 14:26:04 +0100 Subject: [PATCH] Kernel/aarch64: Set Access Permission EL0 bit for userspace mappings This bit was not set, which was causing Permission Faults when executing in userspace. --- Kernel/Arch/aarch64/PageDirectory.h | 10 ++++------ 1 file changed, 4 insertions(+), 6 deletions(-) diff --git a/Kernel/Arch/aarch64/PageDirectory.h b/Kernel/Arch/aarch64/PageDirectory.h index 390a0bc002b..15f02d760db 100644 --- a/Kernel/Arch/aarch64/PageDirectory.h +++ b/Kernel/Arch/aarch64/PageDirectory.h @@ -40,10 +40,8 @@ constexpr u32 INNER_SHAREABLE = (3 << 8); constexpr u32 NORMAL_MEMORY = (0 << 2); constexpr u32 DEVICE_MEMORY = (1 << 2); -constexpr u32 ACCESS_PERMISSION_READWRITE = (0b00 << 6); -constexpr u32 ACCESS_PERMISSION_READWRITE_EL0 = (0b01 << 6); -constexpr u32 ACCESS_PERMISSION_READONLY = (0b10 << 6); -constexpr u32 ACCESS_PERMISSION_READONLY_EL0 = (0b11 << 6); +constexpr u32 ACCESS_PERMISSION_EL0 = (1 << 6); +constexpr u32 ACCESS_PERMISSION_READONLY = (1 << 7); // Figure D5-15 of Arm Architecture Reference Manual Armv8 - page D5-2588 class PageDirectoryEntry { @@ -127,8 +125,8 @@ public: bool is_present() const { return (raw() & Present) == Present; } void set_present(bool b) { set_bit(Present, b); } - bool is_user_allowed() const { TODO_AARCH64(); } - void set_user_allowed(bool) { } + bool is_user_allowed() const { return (raw() & ACCESS_PERMISSION_EL0) == ACCESS_PERMISSION_EL0; } + void set_user_allowed(bool b) { set_bit(ACCESS_PERMISSION_EL0, b); } bool is_writable() const { return !((raw() & ACCESS_PERMISSION_READONLY) == ACCESS_PERMISSION_READONLY); } void set_writable(bool b) { set_bit(ACCESS_PERMISSION_READONLY, !b); }