[PATCH] uml: Fix sysrq-r support for skas mode

The old code had the IP and SP coming from the registers in the thread
struct, which are completely wrong since those are the userspace
registers.  This fixes that by pulling the correct values from the
jmp_buf in which the kernel state of each thread is stored.

Signed-off-by: Allan Graves <allan.graves@oracle.com>
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

3 files changed, 17 insertions, 35 deletions

diff --git a/include/asm-um/processor-generic.h b/include/asm-um/processor-generic.h
index 2d24236..075771c 100644
--- a/include/asm-um/processor-generic.h
+++ b/include/asm-um/processor-generic.h
@@ -13,6 +13,7 @@ struct task_struct;
 #include "linux/config.h"
 #include "asm/ptrace.h"
 #include "choose-mode.h"
+#include "registers.h"
 
 struct mm_struct;
 
@@ -136,19 +137,15 @@ extern struct cpuinfo_um cpu_data[];
 #define current_cpu_data boot_cpu_data
 #endif
 
-#define KSTK_EIP(tsk) (PT_REGS_IP(&tsk->thread.regs))
-#define KSTK_ESP(tsk) (PT_REGS_SP(&tsk->thread.regs))
-#define get_wchan(p) (0)
 
+#ifdef CONFIG_MODE_SKAS
+#define KSTK_REG(tsk, reg) \
+	({ union uml_pt_regs regs; \
+	   get_thread_regs(&regs, tsk->thread.mode.skas.switch_buf); \
+	   UPT_REG(&regs, reg); })
+#else
+#define KSTK_REG(tsk, reg) (0xbadbabe)
 #endif
+#define get_wchan(p) (0)
 
-/*
- * Overrides for Emacs so that we follow Linus's tabbing style.
- * Emacs will notice this stuff at the end of the file and automatically
- * adjust the settings for this buffer only.  This must remain at the end
- * of the file.
- * ---------------------------------------------------------------------------
- * Local variables:
- * c-file-style: "linux"
- * End:
- */
+#endif
diff --git a/include/asm-um/processor-i386.h b/include/asm-um/processor-i386.h
index 431bad3..4108a57 100644
--- a/include/asm-um/processor-i386.h
+++ b/include/asm-um/processor-i386.h
@@ -43,17 +43,10 @@ static inline void rep_nop(void)
 #define ARCH_IS_STACKGROW(address) \
        (address + 32 >= UPT_SP(&current->thread.regs.regs))
 
+#define KSTK_EIP(tsk) KSTK_REG(tsk, EIP)
+#define KSTK_ESP(tsk) KSTK_REG(tsk, UESP)
+#define KSTK_EBP(tsk) KSTK_REG(tsk, EBP)
+
 #include "asm/processor-generic.h"
 
 #endif
-
-/*
- * Overrides for Emacs so that we follow Linus's tabbing style.
- * Emacs will notice this stuff at the end of the file and automatically
- * adjust the settings for this buffer only.  This must remain at the end
- * of the file.
- * ---------------------------------------------------------------------------
- * Local variables:
- * c-file-style: "linux"
- * End:
- */
diff --git a/include/asm-um/processor-x86_64.h b/include/asm-um/processor-x86_64.h
index 0beb9a4..e1e1255 100644
--- a/include/asm-um/processor-x86_64.h
+++ b/include/asm-um/processor-x86_64.h
@@ -36,17 +36,9 @@ extern inline void rep_nop(void)
 #define ARCH_IS_STACKGROW(address) \
         (address + 128 >= UPT_SP(&current->thread.regs.regs))
 
+#define KSTK_EIP(tsk) KSTK_REG(tsk, RIP)
+#define KSTK_ESP(tsk) KSTK_REG(tsk, RSP)
+
 #include "asm/processor-generic.h"
 
 #endif
-
-/*
- * Overrides for Emacs so that we follow Linus's tabbing style.
- * Emacs will notice this stuff at the end of the file and automatically
- * adjust the settings for this buffer only.  This must remain at the end
- * of the file.
- * ---------------------------------------------------------------------------
- * Local variables:
- * c-file-style: "linux"
- * End:
- */