diff options
| author | David Woodhouse <dwmw2@infradead.org> | 2007-06-16 10:48:19 +0100 |
|---|---|---|
| committer | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2007-06-16 09:39:05 -0700 |
| commit | f4d2781731e846c2f01dd85e71883d120860c6dd (patch) | |
| tree | aac469bb1017619d0c314b6efcbbb465196237d6 /drivers/char | |
| parent | de7f928ca460005086a8296be07c217aac4b625d (diff) | |
| download | linux-f4d2781731e846c2f01dd85e71883d120860c6dd.tar.bz2 | |
fix radeon setparam on 32/64 systems, harder.
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 <dwmw2@infradead.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Dave Airlie <airlied@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'drivers/char')
| -rw-r--r-- | drivers/char/drm/radeon_ioc32.c | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/drivers/char/drm/radeon_ioc32.c b/drivers/char/drm/radeon_ioc32.c index 04126c2e79ab..56decda2a71f 100644 --- a/drivers/char/drm/radeon_ioc32.c +++ b/drivers/char/drm/radeon_ioc32.c @@ -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); } +#else +#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, |