linux-stable.git/arch/mips/kernel, branch linux-2.6.32.y

MIPS: Fix restart of indirect syscalls

2016-01-29T21:12:56+00:00

commit e967ef022e00bb7c2e5b1a42007abfdd52055050 upstream.

When 32-bit MIPS userspace invokes a syscall indirectly via syscall(number,
arg1, ..., arg7), the kernel looks up the actual syscall based on the given
number, shifts the other arguments to the left, and jumps to the syscall.

If the syscall is interrupted by a signal and indicates it needs to be
restarted by the kernel (by returning ERESTARTNOINTR for example), the
syscall must be called directly, since the number is no longer the first
argument, and the other arguments are now staged for a direct call.

Before shifting the arguments, store the syscall number in pt_regs->regs[2].
This gets copied temporarily into pt_regs->regs[0] after the syscall returns.
If the syscall needs to be restarted, handle_signal()/do_signal() copies the
number back to pt_regs->reg[2], which ends up in $v0 once control returns to
userspace.

Signed-off-by: Ed Swierk 
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/8929/
Signed-off-by: Ralf Baechle 
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings 
(cherry picked from commit 08f865bba9c705aef95268a33393698e5385587e)
Signed-off-by: Willy Tarreau

MIPS: Cleanup flags in syscall flags handlers.

2014-11-23T09:55:32+00:00

This will simplify further modifications.

Signed-off-by: Ralf Baechle 
(cherry picked from commit e7f3b48af7be9f8007a224663a5b91340626fed5)
[wt: this patch is only there to ease integration of next one]
Signed-off-by: Willy Tarreau

kbuild: Fix gcc -x syntax

2013-06-10T09:42:14+00:00

This is upstream commit b1e0d8b70fa31821ebca3965f2ef8619d7c5e316
backported to the 2.6.32.x stable branch.

The correct syntax for gcc -x is "gcc -x assembler", not
"gcc -xassembler". Even though the latter happens to work, the former
is what is documented in the manual page and thus what gcc wrappers
such as icecream do expect.

This isn't a cosmetic change. The missing space prevents icecream from
recognizing compilation tasks it can't handle, leading to silent kernel
miscompilations.

Besides me, credits go to Michael Matz and Dirk Mueller for
investigating the miscompilation issue and tracking it down to this
incorrect -x parameter syntax.

Signed-off-by: Jean Delvare 
Cc: stable@vger.kernel.org
Cc: Bernhard Walle 
Cc: Michal Marek 
Cc: Ralf Baechle 
Signed-off-by: Willy Tarreau

MIPS: Properly align the .data..init_task section.

2012-10-07T21:37:59+00:00

commit 7b1c0d26a8e272787f0f9fcc5f3e8531df3b3409 upstream.

Improper alignment can lead to unbootable systems and/or random
crashes.

[ralf@linux-mips.org: This is a lond standing bug since
6eb10bc9e2deab06630261cd05c4cb1e9a60e980 (kernel.org) rsp.
c422a10917f75fd19fa7fe070aaaa23e384dae6f (lmo) [MIPS: Clean up linker script
using new linker script macros.] so dates back to 2.6.32.]

Signed-off-by: David Daney 
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/3881/
Signed-off-by: Ralf Baechle 
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Willy Tarreau

untangle the do_mremap() mess

2010-01-18T18:19:11+00:00

This backports the following upstream commits all as one patch:
	54f5de709984bae0d31d823ff03de755f9dcac54
	ecc1a8993751de4e82eb18640d631dae1f626bd6
	1a0ef85f84feb13f07b604fcf5b90ef7c2b5c82f
	f106af4e90eadd76cfc0b5325f659619e08fb762
	097eed103862f9c6a97f2e415e21d1134017b135
	935874141df839c706cd6cdc438e85eb69d1525e
	0ec62d290912bb4b989be7563851bc364ec73b56
	c4caa778157dbbf04116f0ac2111e389b5cd7a29
	2ea1d13f64efdf49319e86c87d9ba38c30902782
	570dcf2c15463842e384eb597a87c1e39bead99b
	564b3bffc619dcbdd160de597b0547a7017ea010
	0067bd8a55862ac9dd212bd1c4f6f5bff1ca1301
	f8b7256096a20436f6d0926747e3ac3d64c81d24
	8c7b49b3ecd48923eb64ff57e07a1cdb74782970
	9206de95b1ea68357996ec02be5db0638a0de2c1
	2c6a10161d0b5fc047b5bd81b03693b9af99fab5
	05d72faa6d13c9d857478a5d35c85db9adada685
	bb52d6694002b9d632bb355f64daa045c6293a4e
	e77414e0aad6a1b063ba5e5750c582c75327ea6a
	aa65607373a4daf2010e8c3867b6317619f3c1a3

Backport done by Greg Kroah-Hartman.  Only minor tweaks were needed.

Cc: David S. Miller 
Cc: Hugh Dickins 
Cc: Paul Mundt 
Cc: Russell King 
Cc: Linus Torvalds 
Signed-off-by: Al Viro 
Signed-off-by: Greg Kroah-Hartman

MIPS: Fix MIPS I build.

2009-12-02T18:09:51+00:00

Broken by d63c63e889bbeeaa461a8addf1245f89f3ce4ece (lmo) rsp.
f1e39a4a616cd9981a9decfd5332fd07a01abb8b (kernel.org).

Signed-off-by: Ralf Baechle 
Patchwork: http://patchwork.linux-mips.org/patch/746/

MIPS: SMTC: Fix lockup in smtc_distribute_timer

2009-11-13T17:10:38+00:00

1. At the end of smtc_distribute_timer, nextstamp is valid and has already
   passed so we goto repeat.
2. Nothing updates nextstamp (only updated if the timeout is in the future
   And we just decided it is in the past)
3. At the end nextstamp still has the same value so it is still valid and
   in the past.
4. This repeats until read_c0_count has a value which causes nextstamp to
   be in the future.

Reported and initial patch and testing  by Mikael Starvik
.

Signed-off-by: Kevin D. Kissell 
Cc: Mikael Starvik 
Cc: linux-mips@linux-mips.org
Cc: Jesper Nilsson 
Patchwork: http://patchwork.linux-mips.org/patch/621/
Signed-off-by: Ralf Baechle

MIPS: O32: Fix ppoll

2009-11-02T11:00:08+00:00

sys_ppoll syscall needs to use a compat handler on 64bit kernels with o32
user-space.

Signed-off-by: Arnaud Patard 
Signed-off-by: Ralf Baechle

MIPS: Avoid potential hazard on Context register

2009-11-02T11:00:07+00:00

set_saved_sp reads Context register. Avoid reading stale value from
earlier incomplete write.

Issue found and fixed for head.S by Chris Dearman .

Signed-off-by: Chris Dearman 
Signed-off-by: Ralf Baechle

MIPS: SMTC: Avoid queing multiple reschedule IPIs

2009-11-02T11:00:06+00:00

Signed-off-by: Chris Dearman 
Signed-off-by: Ralf Baechle