fix radeon setparam on 32/64 systems, harder.
authorDavid Woodhouse <>
Sat, 16 Jun 2007 09:48:19 +0000 (10:48 +0100)
committerLinus Torvalds <>
Sat, 16 Jun 2007 16:39:05 +0000 (09:39 -0700)
Commit 9b01bd5b284bbf519b726b39f1352023cb5e9e69 introduced a
compat_ioctl handler for RADEON_SETPARAM, the sole purpose of which was
to handle the fact that on i386, alignof(uint64_t)==4.

Unfortunately, this handler was installed for _all_ 64-bit
architectures, instead of only x86_64 and ia64.  And thus it breaks
32-bit compatibility on every other arch, where 64-bit integers are
aligned to 8 bytes in 32-bit mode just the same as in 64-bit mode.

Arnd has a cunning plan to use 'compat_u64' with appropriate alignment
attributes according to the 32-bit ABI, but for now let's just make the
compat_radeon_cp_setparam routine entirely disappear on 64-bit machines
whose 32-bit compat support isn't for i386.  It would be a no-op with
compat_u64 anyway.

Signed-off-by: David Woodhouse <>
Acked-by: Arnd Bergmann <>
Cc: Benjamin Herrenschmidt <>
Cc: Dave Airlie <>
Signed-off-by: Linus Torvalds <>

index 04126c2e79ab71b5ef8513898466d2004a9d4a4c..56decda2a71ff20af100dde0dd959353be189c9e 100644 (file)
@@ -349,6 +349,8 @@ static int compat_radeon_irq_emit(struct file *file, unsigned int cmd,
                         DRM_IOCTL_RADEON_IRQ_EMIT, (unsigned long)request);
+/* The two 64-bit arches where alignof(u64)==4 in 32-bit code */
+#if defined (CONFIG_X86_64) || defined(CONFIG_IA64)
 typedef struct drm_radeon_setparam32 {
        int param;
        u64 value;
@@ -373,6 +375,9 @@ static int compat_radeon_cp_setparam(struct file *file, unsigned int cmd,
        return drm_ioctl(file->f_dentry->d_inode, file,
                         DRM_IOCTL_RADEON_SETPARAM, (unsigned long) request);
+#define compat_radeon_cp_setparam NULL
+#endif /* X86_64 || IA64 */
 drm_ioctl_compat_t *radeon_compat_ioctls[] = {
        [DRM_RADEON_CP_INIT] = compat_radeon_cp_init,