linux-stable.git/arch/xtensa/kernel/process.c, branch v3.7

xtensa: switch to generic sys_execve()

2012-10-25T22:00:44+00:00

Signed-off-by: Max Filippov 
Signed-off-by: Chris Zankel

xtensa: switch to generic kernel_thread()

2012-10-25T22:00:03+00:00

Signed-off-by: Max Filippov 
Signed-off-by: Chris Zankel

xtensa: reset windowbase/windowstart when cloning the VM

2012-10-25T21:53:36+00:00

When we copy a user thread with CLONE_VM, we also have to reset
windowbase and windowstart to start a pristine stack frame. Otherwise,
overflows can happen using the address 0 as the stack pointer.
Also add a special case for vfork, which continues on the
parent stack until it calls execve. Because this could be a call8, we
need to spill the stack pointer of the previus frame (if still 'live' in
the register file).

Signed-off-by: Chris Zankel

xtensa: minor compiler warning fix

2012-10-19T17:24:20+00:00

Fix two compiler warnings complaining about truncating a value on
a 64-bit host, and about declaring an unused variable that is only
used for a specific configuration.

Signed-off-by: Chris Zankel

xtensa: copy_thread with CLONE_VM must not copy live parent AR windows

2012-10-16T04:42:27+00:00

When doing a fork (new VM), the new task has a mirror image of the
parent's stack, so keeps the same live register windows etc.
However when doing a clone with CLONE_VM, keeping the same VM
(eg. when creating a new thread), the child starts afresh on a new
stack -- it cannot share any part of the parent stack.  It
especially cannot have the same live AR windows as the parent,
otherwise it will overwrite the parent stack on overflow, likely
causing corruption.  (and so it did...)

Effectively, the register windows need to be spilled.
Turns out it's much easier to simply not copy parent register
windows when CLONE_VM is set.

Signed-off-by: Marc Gauthier 
Signed-off-by: Max Filippov 
Signed-off-by: Chris Zankel

vfs: define struct filename and have getname() return it

2012-10-13T00:14:55+00:00

getname() is intended to copy pathname strings from userspace into a
kernel buffer. The result is just a string in kernel space. It would
however be quite helpful to be able to attach some ancillary info to
the string.

For instance, we could attach some audit-related info to reduce the
amount of audit-related processing needed. When auditing is enabled,
we could also call getname() on the string more than once and not
need to recopy it from userspace.

This patchset converts the getname()/putname() interfaces to return
a struct instead of a string. For now, the struct just tracks the
string in kernel space and the original userland pointer for it.

Later, we'll add other information to the struct as it becomes
convenient.

Signed-off-by: Jeff Layton 
Signed-off-by: Al Viro

xtensa: Add missing RCU idle APIs on idle loop

2012-09-23T14:44:51+00:00

In the old times, the whole idle task was considered
as an RCU quiescent state. But as RCU became more and
more successful overtime, some RCU read side critical
section have been added even in the code of some
architectures idle tasks, for tracing for example.

So nowadays, rcu_idle_enter() and rcu_idle_exit() must
be called by the architecture to tell RCU about the part
in the idle loop that doesn't make use of rcu read side
critical sections, typically the part that puts the CPU
in low power mode.

This is necessary for RCU to find the quiescent states in
idle in order to complete grace periods.

Add this missing pair of calls in the xtensa's idle loop.

Reported-by: Paul E. McKenney 
Signed-off-by: Frederic Weisbecker 
Cc: Chris Zankel 
Cc:  # 3.3+
Signed-off-by: Paul E. McKenney 
Reviewed-by: Josh Triplett

xtensa: fix incorrect memset

2012-07-11T23:04:49+00:00

Addresses: https://bugzilla.kernel.org/show_bug.cgi?id=43871

Reported-by: 
Signed-off-by: Alan Cox 
Signed-off-by: Chris Zankel 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

fork: move the real prepare_to_copy() users to arch_dup_task_struct()

2012-05-16T22:16:26+00:00

Historical prepare_to_copy() is mostly a no-op, duplicated for majority of
the architectures and the rest following the x86 model of flushing the extended
register state like fpu there.

Remove it and use the arch_dup_task_struct() instead.

Suggested-by: Oleg Nesterov 
Suggested-by: Linus Torvalds 
Signed-off-by: Suresh Siddha 
Link: http://lkml.kernel.org/r/1336692811-30576-1-git-send-email-suresh.b.siddha@intel.com
Acked-by: Benjamin Herrenschmidt 
Cc: David Howells 
Cc: Koichi Yasutake 
Cc: Paul Mackerras 
Cc: Paul Mundt 
Cc: Chris Zankel 
Cc: Richard Henderson 
Cc: Russell King 
Cc: Haavard Skinnemoen 
Cc: Mike Frysinger 
Cc: Mark Salter 
Cc: Aurelien Jacquiot 
Cc: Mikael Starvik 
Cc: Yoshinori Sato 
Cc: Richard Kuo 
Cc: Tony Luck 
Cc: Michal Simek 
Cc: Ralf Baechle 
Cc: Jonas Bonn 
Cc: James E.J. Bottomley 
Cc: Helge Deller 
Cc: Martin Schwidefsky 
Cc: Heiko Carstens 
Cc: Chen Liqin 
Cc: Lennox Wu 
Cc: David S. Miller 
Cc: Chris Metcalf 
Cc: Jeff Dike 
Cc: Richard Weinberger 
Cc: Guan Xuetao 
Signed-off-by: H. Peter Anvin

Disintegrate asm/system.h for Xtensa

2012-03-28T17:30:03+00:00

Disintegrate asm/system.h for Xtensa.

Signed-off-by: David Howells 
cc: Chris Zankel