linux-kernel - [Patch 4/10] Introduce virtual debug register in thread_struct and wrapper-routines around process related functions

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Thu, 29 Jan 2009 13:58:29 +0530
From:	"K.Prasad" <prasad@...ux.vnet.ibm.com>
To:	akpm@...ux-foundation.org,
	Linux Kernel Mailing List <linux-kernel@...r.kernel.org>
Cc:	Alan Stern <stern@...land.harvard.edu>,
	Roland McGrath <roland@...hat.com>, mingo@...e.hu,
	richardj_moore@...ibm.com, jason.wessel@...driver.com
Subject: [Patch 4/10] Introduce virtual debug register in thread_struct and
	wrapper-routines around process related functions

This patch introduces virtual debug registers to used by the per-thread
structure ad wrapper routines to manage debug registers by process-related
functions.

Signed-off-by: K.Prasad <prasad@...ux.vnet.ibm.com>
Signed-off-by: Alan Stern <stern@...land.harvard.edu>
---
 arch/x86/include/asm/debugreg.h  |   27 +++++++++++++++++++++++++++
 arch/x86/include/asm/processor.h |   10 +++-------
 2 files changed, 30 insertions(+), 7 deletions(-)

Index: linux-hbkpt-lkml-29-rc2/arch/x86/include/asm/debugreg.h
===================================================================
--- linux-hbkpt-lkml-29-rc2.orig/arch/x86/include/asm/debugreg.h
+++ linux-hbkpt-lkml-29-rc2/arch/x86/include/asm/debugreg.h
@@ -49,6 +49,8 @@
 
 #define DR_LOCAL_ENABLE_SHIFT 0    /* Extra shift to the local enable bit */
 #define DR_GLOBAL_ENABLE_SHIFT 1   /* Extra shift to the global enable bit */
+#define DR_LOCAL_ENABLE (0x1)      /* Local enable for reg 0 */
+#define DR_GLOBAL_ENABLE (0x2)     /* Global enable for reg 0 */
 #define DR_ENABLE_SIZE 2           /* 2 enable bits per register */
 
 #define DR_LOCAL_ENABLE_MASK (0x55)  /* Set  local bits for all 4 regs */
@@ -67,4 +69,29 @@
 #define DR_LOCAL_SLOWDOWN (0x100)   /* Local slow the pipeline */
 #define DR_GLOBAL_SLOWDOWN (0x200)  /* Global slow the pipeline */
 
+/*
+ * HW breakpoint additions
+ */
+#ifdef __KERNEL__
+
+/* For process management */
+void flush_thread_hw_breakpoint(struct task_struct *tsk);
+int copy_thread_hw_breakpoint(struct task_struct *tsk,
+		struct task_struct *child, unsigned long clone_flags);
+void dump_thread_hw_breakpoint(struct task_struct *tsk, int u_debugreg[8]);
+void switch_to_thread_hw_breakpoint(struct task_struct *tsk);
+
+/* For CPU management */
+void load_debug_registers(void);
+static inline void disable_debug_registers(void)
+{
+	set_debugreg(0UL, 7);
+}
+
+/* For use by ptrace */
+unsigned long thread_get_debugreg(struct task_struct *tsk, int n);
+int thread_set_debugreg(struct task_struct *tsk, int n, unsigned long val);
+
+#endif	/* __KERNEL__ */
+
 #endif /* _ASM_X86_DEBUGREG_H */
Index: linux-hbkpt-lkml-29-rc2/arch/x86/include/asm/processor.h
===================================================================
--- linux-hbkpt-lkml-29-rc2.orig/arch/x86/include/asm/processor.h
+++ linux-hbkpt-lkml-29-rc2/arch/x86/include/asm/processor.h
@@ -405,13 +405,9 @@ struct thread_struct {
 	unsigned long		ip;
 	unsigned long		fs;
 	unsigned long		gs;
-	/* Hardware debugging registers: */
-	unsigned long		debugreg0;
-	unsigned long		debugreg1;
-	unsigned long		debugreg2;
-	unsigned long		debugreg3;
-	unsigned long		debugreg6;
-	unsigned long		debugreg7;
+/* Hardware breakpoint info */
+	unsigned long	vdr6;
+	struct thread_hw_breakpoint	*hw_breakpoint_info;
 	/* Fault info: */
 	unsigned long		cr2;
 	unsigned long		trap_no;
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/