linux-toradex.git/kernel/compat.c, branch v2.6.18.8

[PATCH] N32 sigset and __COMPAT_ENDIAN_SWAP__

2006-06-25T17:01:15+00:00

I'm testing glibc on MIPS64, little-endian, N32, O32 and N64 multilibs.

Among the NPTL test failures seen are some arising from sigsuspend problems
for N32: it blocks the wrong signals, so SIGCANCEL (SIGRTMIN) is blocked
despite glibc's carefully excluding it from sets of signals to block.
Specifically, testing suggests it blocks signal N^32 instead of signal N,
so (in the example tested) blocking SIGUSR1 (17) blocks signal 49 instead.

glibc's sigset_t uses an array of unsigned long, as does the kernel.
In both cases, signal N+1 is represented as
(1UL << (N % (8 * sizeof (unsigned long)))) in word number
(N / (8 * sizeof (unsigned long))).

Thus the N32 glibc uses an array of 32-bit words and the N64 kernel uses an
array of 64-bit words.  For little-endian, the layout is the same, with
signals 1-32 in the first 4 bytes, signals 33-64 in the second, etc.; for
big-endian, userspace has that layout while in the kernel each 8 bytes have
the two halves swapped from the userspace layout.

The N32 sigsuspend syscall uses sigset_from_compat to convert the userspace
sigset to kernel format.  If __COMPAT_ENDIAN_SWAP__ is *not* set, this uses
logic of the form

  set->sig[0] = compat->sig[0] | (((long)compat->sig[1]) << 32 )

to convert the userspace sigset to a kernel one.  This looks correct to me
for both big and little endian, given that in userspace compat->sig[1] will
represent signals 33-64, and so will the high 32 bits of set->sig[0] in the
kernel.  If however __COMPAT_ENDIAN_SWAP__ *is* set, as it is for
__MIPSEL__, it uses

  set->sig[0] = compat->sig[1] | (((long)compat->sig[0]) << 32 );

which seems incorrect for both big and little endian, and would
explain the observed symptoms.

This code is the only use of __COMPAT_ENDIAN_SWAP__, so if incorrect
then that macro serves no purpose, in which case something like the
following patch would seem appropriate to remove it.

Signed-off-by: Joseph Myers 
Signed-off-by: Ralf Baechle 
Cc: Arnd Bergmann 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] move_pages: fix 32 -> 64 bit compat function

2006-06-23T14:42:53+00:00

The definition of the third parameter is a pointer to an array of virtual
addresses which give us some trouble.  The existing code calculated the
wrong address in the array since I used void to avoid having to specify a
type.

I now use the correct type "compat_uptr_t __user *" in the definition of
the function in kernel/compat.c.

However, I used __u32 in syscalls.h.  Would have to include compat.h there
in order to provide the same definition which would generate an ugly
include situation.

On both ia64 and x86_64 compat_uptr_t is u32. So this works although
parameter declarations differ.

Signed-off-by: Christoph Lameter 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] sys_move_pages: 32bit support (i386, x86_64)

2006-06-23T14:42:53+00:00

sys_move_pages() support for 32bit (i386 plus x86_64 compat layer)

Add support for move_pages() on i386 and also add the compat functions
necessary to run 32 bit binaries on x86_64.

Add compat_sys_move_pages to the x86_64 32bit binary layer.  Note that it is
not up to date so I added the missing pieces.  Not sure if this is done the
right way.

[akpm@osdl.org: compile fix]
Signed-off-by: Christoph Lameter 
Cc: Andi Kleen 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] lightweight robust futexes: compat

2006-03-27T16:44:49+00:00

32-bit syscall compatibility support.  (This patch also moves all futex
related compat functionality into kernel/futex_compat.c.)

Signed-off-by: Ingo Molnar 
Signed-off-by: Thomas Gleixner 
Signed-off-by: Arjan van de Ven 
Acked-by: Ulrich Drepper 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] consolidate sys32/compat_adjtimex

2006-03-26T16:56:57+00:00

Create compat_sys_adjtimex and use it an all appropriate places.

Signed-off-by: Stephen Rothwell 
Cc: Arnd Bergmann 
Acked-by: Paul Mackerras 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] remove bogus asm/bug.h includes.

2006-02-08T01:56:35+00:00

A bunch of asm/bug.h includes are both not needed (since it will get
pulled anyway) and bogus (since they are done too early).  Removed.

Signed-off-by: Al Viro

[PATCH] Generic sys_rt_sigsuspend()

2006-01-19T03:20:29+00:00

The TIF_RESTORE_SIGMASK flag allows us to have a generic implementation of
sys_rt_sigsuspend() instead of duplicating it for each architecture.  This
provides such an implementation and makes arch/powerpc use it.

It also tidies up the ppc32 sys_sigsuspend() to use TIF_RESTORE_SIGMASK.

Signed-off-by: David Woodhouse 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] common compat_sys_timer_create

2006-01-10T16:01:32+00:00

The comment in compat.c is wrong, every architecture provides a
get_compat_sigevent() for the IPC compat code already.

This basically moves the x86_64 version to common code and removes all the
others.

Signed-off-by: Christoph Hellwig 
Acked-by: Paul Mackerras 
Cc: Arnd Bergmann 
Cc: Benjamin Herrenschmidt 
Cc: Martin Schwidefsky 
Cc: "David S. Miller" 
Acked-by: Andi Kleen 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] kernel: fix-up schedule_timeout() usage

2005-09-10T17:06:37+00:00

Use schedule_timeout_{,un}interruptible() instead of
set_current_state()/schedule_timeout() to reduce kernel size.

Signed-off-by: Nishanth Aravamudan 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] Fix get_compat_sigevent()

2005-04-16T22:24:01+00:00

I have no idea how a bug like this lasted so long.  Anyways, obvious
memset()'ing of incorrect pointer.

Signed-off-by: David S. Miller 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds