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Fix powerpc32 __get_clockfreq for non-power4 (bug 17263)


In my powerpc32 testing I've observed misc/test-gettimebasefreq
failing.

This is a glibc build (soft-float, though that's not relevant here)
without any --with-cpu and without any special configuration of the
default CPU for GCC either.  In particular, it's one not using
sysdeps/powerpc/powerpc32/power4/hp-timing.h (although in fact the
processor I'm using for testing is POWER4-based), so hp_timing_t is
32-bit not 64-bit.  But the VDSO call being used by
INTERNAL_VSYSCALL_NO_SYSCALL_FALLBACK is generating a 64-bit result
(high part in r3, low part in r4).  The code extracting that result,
however, expects a result of the type hp_timing_t as passed to
INTERNAL_VSYSCALL_NO_SYSCALL_FALLBACK, meaning that only r3 (= 0) is
used and the value in r4 is ignored.  This patch fixes this by always
using uint64_t as the type in INTERNAL_VSYSCALL_NO_SYSCALL_FALLBACK -
reflecting the actual ABI (unconditional in the kernel) of that VDSO
call.  This is the minimal change for this issue - no check for
overflow, no change of the type of the timebase_freq variable or the
return type of __get_clockfreq to something other than hp_timing_t
(such a change would simply move the implicit conversions to the over
callers of that function), no change to hp_timing_t itself.

Tested for powerpc32 soft float.

2014-08-12  Joseph Myers  <joseph@codesourcery.com>

	[BZ #17263]
	* sysdeps/unix/sysv/linux/powerpc/get_clockfreq.c: Include
	<stdint.h>.
	(__get_clockfreq): Use uint64_t instead of hp_timing_t in
	INTERNAL_VSYSCALL_NO_SYSCALL_FALLBACK call.

diff --git a/sysdeps/unix/sysv/linux/powerpc/get_clockfreq.c b/sysdeps/unix/sysv/linux/powerpc/get_clockfreq.c
index 8b37943..62217b1 100644
--- a/sysdeps/unix/sysv/linux/powerpc/get_clockfreq.c
+++ b/sysdeps/unix/sysv/linux/powerpc/get_clockfreq.c
@@ -18,6 +18,7 @@
 
 #include <ctype.h>
 #include <fcntl.h>
+#include <stdint.h>
 #include <string.h>
 #include <unistd.h>
 #include <libc-internal.h>
@@ -42,7 +43,7 @@ __get_clockfreq (void)
 #ifdef SHARED
   INTERNAL_SYSCALL_DECL (err);
   timebase_freq =
-    INTERNAL_VSYSCALL_NO_SYSCALL_FALLBACK (get_tbfreq, err, hp_timing_t, 0);
+    INTERNAL_VSYSCALL_NO_SYSCALL_FALLBACK (get_tbfreq, err, uint64_t, 0);
   if (INTERNAL_SYSCALL_ERROR_P (timebase_freq, err)
       && INTERNAL_SYSCALL_ERRNO (timebase_freq, err) == ENOSYS)
 #endif

-- 
Joseph S. Myers
joseph@codesourcery.com


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