summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorMarkus Metzger <markus.t.metzger@intel.com>2009-04-03 18:43:46 +0400
committerIngo Molnar <mingo@elte.hu>2009-04-07 15:36:28 +0400
commit2311f0de21c17b2a8b960677a9cccfbfa52beb35 (patch)
treebd1f12da337e4f88675f43e71fe6e06016fbc76c
parent3a68eef945b234f286406d96dc690fe17863c203 (diff)
downloadlinux-2311f0de21c17b2a8b960677a9cccfbfa52beb35.tar.xz
x86, ds: add leakage warning
Add a warning in case a debug store context is not removed before the task it is attached to is freed. Remove the old warning at thread exit. It is too early. Declare the debug store context field in thread_struct unconditionally. Remove ds_copy_thread() and ds_exit_thread() and do the work directly in process*.c. Signed-off-by: Markus Metzger <markus.t.metzger@intel.com> Cc: roland@redhat.com Cc: eranian@googlemail.com Cc: oleg@redhat.com Cc: juan.villacis@intel.com Cc: ak@linux.jf.intel.com LKML-Reference: <20090403144601.254472000@intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
-rw-r--r--arch/x86/include/asm/ds.h9
-rw-r--r--arch/x86/include/asm/processor.h4
-rw-r--r--arch/x86/kernel/ds.c10
-rw-r--r--arch/x86/kernel/process.c5
-rw-r--r--arch/x86/kernel/process_32.c3
-rw-r--r--arch/x86/kernel/process_64.c3
6 files changed, 8 insertions, 26 deletions
diff --git a/arch/x86/include/asm/ds.h b/arch/x86/include/asm/ds.h
index 413e127e567d..149e5208e967 100644
--- a/arch/x86/include/asm/ds.h
+++ b/arch/x86/include/asm/ds.h
@@ -285,21 +285,12 @@ extern void __cpuinit ds_init_intel(struct cpuinfo_x86 *);
*/
extern void ds_switch_to(struct task_struct *prev, struct task_struct *next);
-/*
- * Task clone/init and cleanup work
- */
-extern void ds_copy_thread(struct task_struct *tsk, struct task_struct *father);
-extern void ds_exit_thread(struct task_struct *tsk);
-
#else /* CONFIG_X86_DS */
struct cpuinfo_x86;
static inline void __cpuinit ds_init_intel(struct cpuinfo_x86 *ignored) {}
static inline void ds_switch_to(struct task_struct *prev,
struct task_struct *next) {}
-static inline void ds_copy_thread(struct task_struct *tsk,
- struct task_struct *father) {}
-static inline void ds_exit_thread(struct task_struct *tsk) {}
#endif /* CONFIG_X86_DS */
#endif /* _ASM_X86_DS_H */
diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h
index 1efeb497f1f9..7c39de7e709a 100644
--- a/arch/x86/include/asm/processor.h
+++ b/arch/x86/include/asm/processor.h
@@ -454,10 +454,8 @@ struct thread_struct {
unsigned io_bitmap_max;
/* MSR_IA32_DEBUGCTLMSR value to switch in if TIF_DEBUGCTLMSR is set. */
unsigned long debugctlmsr;
-#ifdef CONFIG_X86_DS
-/* Debug Store context; see include/asm-x86/ds.h; goes into MSR_IA32_DS_AREA */
+ /* Debug Store context; see asm/ds.h */
struct ds_context *ds_ctx;
-#endif /* CONFIG_X86_DS */
};
static inline unsigned long native_get_debugreg(int regno)
diff --git a/arch/x86/kernel/ds.c b/arch/x86/kernel/ds.c
index 21a3852abf68..71cab3b62dce 100644
--- a/arch/x86/kernel/ds.c
+++ b/arch/x86/kernel/ds.c
@@ -1352,16 +1352,6 @@ void ds_switch_to(struct task_struct *prev, struct task_struct *next)
update_debugctlmsr(debugctlmsr);
}
-void ds_copy_thread(struct task_struct *tsk, struct task_struct *father)
-{
- clear_tsk_thread_flag(tsk, TIF_DS_AREA_MSR);
- tsk->thread.ds_ctx = NULL;
-}
-
-void ds_exit_thread(struct task_struct *tsk)
-{
-}
-
static __init int ds_selftest(void)
{
if (ds_cfg.sizeof_rec[ds_bts]) {
diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c
index ca989158e847..fb5dfb891f0f 100644
--- a/arch/x86/kernel/process.c
+++ b/arch/x86/kernel/process.c
@@ -14,6 +14,7 @@
#include <asm/idle.h>
#include <asm/uaccess.h>
#include <asm/i387.h>
+#include <asm/ds.h>
unsigned long idle_halt;
EXPORT_SYMBOL(idle_halt);
@@ -45,6 +46,8 @@ void free_thread_xstate(struct task_struct *tsk)
kmem_cache_free(task_xstate_cachep, tsk->thread.xstate);
tsk->thread.xstate = NULL;
}
+
+ WARN(tsk->thread.ds_ctx, "leaking DS context\n");
}
void free_thread_info(struct thread_info *ti)
@@ -83,8 +86,6 @@ void exit_thread(void)
put_cpu();
kfree(bp);
}
-
- ds_exit_thread(current);
}
void flush_thread(void)
diff --git a/arch/x86/kernel/process_32.c b/arch/x86/kernel/process_32.c
index 76f8f84043a2..b5e4bfef4472 100644
--- a/arch/x86/kernel/process_32.c
+++ b/arch/x86/kernel/process_32.c
@@ -290,7 +290,8 @@ int copy_thread(unsigned long clone_flags, unsigned long sp,
p->thread.io_bitmap_max = 0;
}
- ds_copy_thread(p, current);
+ clear_tsk_thread_flag(p, TIF_DS_AREA_MSR);
+ p->thread.ds_ctx = NULL;
clear_tsk_thread_flag(p, TIF_DEBUGCTLMSR);
p->thread.debugctlmsr = 0;
diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c
index b751a41392b1..5a1a1de292ec 100644
--- a/arch/x86/kernel/process_64.c
+++ b/arch/x86/kernel/process_64.c
@@ -335,7 +335,8 @@ int copy_thread(unsigned long clone_flags, unsigned long sp,
goto out;
}
- ds_copy_thread(p, me);
+ clear_tsk_thread_flag(p, TIF_DS_AREA_MSR);
+ p->thread.ds_ctx = NULL;
clear_tsk_thread_flag(p, TIF_DEBUGCTLMSR);
p->thread.debugctlmsr = 0;