DR6_RESERVED and DR_CONTROL_RESERVED are used to clear the set
bits in the "unsigned long" data, make them long to ensure that
"&~" doesn't clear the upper bits.

This is only cleanup, the usage of ~DR*_RESERVED is safe but
doesn't look clean and the pattern is error prone.

        - do_debug:

                dr6 &= ~DR6_RESERVED;

          this also wrongly clears 32-63 bits. Fortunately these
          bits are reserved and must be zero.

        - ptrace_write_dr7:

                data &= ~DR_CONTROL_RESERVED;

          on __i386__ this mixes long/int but sizeof should be the
          same.

Reported-by: Linus Torvalds <torva...@linux-foundation.org>
Signed-off-by: Oleg Nesterov <o...@redhat.com>
---
 arch/x86/include/uapi/asm/debugreg.h |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/x86/include/uapi/asm/debugreg.h 
b/arch/x86/include/uapi/asm/debugreg.h
index 3c0874d..c0c1b89 100644
--- a/arch/x86/include/uapi/asm/debugreg.h
+++ b/arch/x86/include/uapi/asm/debugreg.h
@@ -15,7 +15,7 @@
    are either reserved or not of interest to us. */
 
 /* Define reserved bits in DR6 which are always set to 1 */
-#define DR6_RESERVED   (0xFFFF0FF0)
+#define DR6_RESERVED   (0xFFFF0FF0UL)
 
 #define DR_TRAP0       (0x1)           /* db0 */
 #define DR_TRAP1       (0x2)           /* db1 */
@@ -65,7 +65,7 @@
    gdt or the ldt if we want to.  I am not sure why this is an advantage */
 
 #ifdef __i386__
-#define DR_CONTROL_RESERVED (0xFC00) /* Reserved by Intel */
+#define DR_CONTROL_RESERVED (0xFC00UL) /* Reserved by Intel */
 #else
 #define DR_CONTROL_RESERVED (0xFFFFFFFF0000FC00UL) /* Reserved */
 #endif
-- 
1.5.5.1


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