From 60923df35edab273d0bd8e829cdfdc5cfbb4fd2c Mon Sep 17 00:00:00 2001 From: Chuck Ebbert <76306.1226@compuserve.com> Date: Wed, 11 Jan 2006 22:46:03 +0100 Subject: [PATCH] [PATCH] x86_64: allow setting RF in EFLAGS Setting RF (resume flag) allows a debugger to resume execution after a code breakpoint without tripping the breakpoint again. It is reset by the CPU after executing one instruction. Signed-off-by: Chuck Ebbert <76306.1226@compuserve.com> Signed-off-by: Andi Kleen Signed-off-by: Linus Torvalds --- arch/x86_64/ia32/ptrace32.c | 9 ++++++--- arch/x86_64/kernel/ptrace.c | 9 ++++++--- 2 files changed, 12 insertions(+), 6 deletions(-) diff --git a/arch/x86_64/ia32/ptrace32.c b/arch/x86_64/ia32/ptrace32.c index 5f4cdfa56901..ea4394e021d6 100644 --- a/arch/x86_64/ia32/ptrace32.c +++ b/arch/x86_64/ia32/ptrace32.c @@ -28,9 +28,12 @@ #include #include -/* determines which flags the user has access to. */ -/* 1 = access 0 = no access */ -#define FLAG_MASK 0x44dd5UL +/* + * Determines which flags the user has access to [1 = access, 0 = no access]. + * Prohibits changing ID(21), VIP(20), VIF(19), VM(17), IOPL(12-13), IF(9). + * Also masks reserved bits (31-22, 15, 5, 3, 1). + */ +#define FLAG_MASK 0x54dd5UL #define R32(l,q) \ case offsetof(struct user32, regs.l): stack[offsetof(struct pt_regs, q)/8] = val; break diff --git a/arch/x86_64/kernel/ptrace.c b/arch/x86_64/kernel/ptrace.c index a87b6cebe80f..86248bc9303e 100644 --- a/arch/x86_64/kernel/ptrace.c +++ b/arch/x86_64/kernel/ptrace.c @@ -36,9 +36,12 @@ * in exit.c or in signal.c. */ -/* determines which flags the user has access to. */ -/* 1 = access 0 = no access */ -#define FLAG_MASK 0x44dd5UL +/* + * Determines which flags the user has access to [1 = access, 0 = no access]. + * Prohibits changing ID(21), VIP(20), VIF(19), VM(17), IOPL(12-13), IF(9). + * Also masks reserved bits (63-22, 15, 5, 3, 1). + */ +#define FLAG_MASK 0x54dd5UL /* set's the trap flag. */ #define TRAP_FLAG 0x100UL -- 2.20.1