Граф коммитов

36 Коммитов

Автор SHA1 Сообщение Дата
Kuninori Morimoto 5933f6d220 sh: kernel: convert to SPDX identifiers
Update license to use SPDX-License-Identifier instead of verbose license
text.

Link: http://lkml.kernel.org/r/8736rccswn.wl-kuninori.morimoto.gx@renesas.com
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Cc: Rich Felker <dalias@libc.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-12-28 12:11:45 -08:00
Rich Felker 96a598996f sh: fix debug trap failure to process signals before return to user
When responding to a debug trap (breakpoint) in userspace, the
kernel's trap handler raised SIGTRAP but returned from the trap via a
code path that ignored pending signals, resulting in an infinite loop
re-executing the trapping instruction.

Signed-off-by: Rich Felker <dalias@libc.org>
2018-04-12 19:47:52 -04:00
Rich Felker 3623d13821 sh: provide unified syscall trap compatible with all SH models
Historically SH-2 Linux (and originally uClinux) used a syscall
calling convention incompatible with the established SH-3/4 Linux ABI.
This choice was made because the trap range used by the existing ABI,
0x10-0x17, overlaps with the hardware exception/interrupt trap range
reserved by SH-2, and in particular, with the SH-2A divide-by-zero and
division-overflow exceptions.

Despite the documented syscall convention using the low bits of the
trap number to signal the number of arguments the kernel should
expect, no version of the kernel has ever used this information, nor
is it useful; all of the registers need to be saved anyway. Therefore,
it is possible to pick a new trap number, 0x1f, that is both supported
by all existing SH-3/4 kernels and unassigned as a hardware trap in
the SH-2 range. This makes it possible to produce SH-2 application
binaries that are forwards-compatible with running on SH-3/4 kernels
and to treat SH as a unified platform with varying ISA support levels
rather than multiple gratuitously-incompatible platforms.

This patch adjusts the range checking SH-2 and SH-2A kernels make for
the syscall trap to accept the range 0x1f-0x2f rather than just
0x20-0x2f. As a result, trap 0x1f now acts as a syscall for all SH
models.

Signed-off-by: Rich Felker <dalias@libc.org>
2016-03-17 19:46:06 +00:00
Bobby Bingham abafe5d9b0 sh: push extra copy of r0-r2 for syscall parameters
When invoking syscall handlers on sh32, the saved userspace registers
are at the top of the stack.  This seems to have been intentional, as it
is an easy way to pass r0, r1, ...  to the handler as parameters 5, 6,
...

It causes problems, however, because the compiler is allowed to generate
code for a function which clobbers that function's own parameters.  For
example, gcc generates the following code for clone:

    <SyS_clone>:
        mov.l   8c020714 <SyS_clone+0xc>,r1  ! 8c020540 <do_fork>
        mov.l   r7,@r15
        mov     r6,r7
        jmp     @r1
        mov     #0,r6
        nop
        .word 0x0540
        .word 0x8c02

The `mov.l r7,@r15` clobbers the saved value of r0 passed from
userspace.  For most system calls, this might not be a problem, because
we'll be overwriting r0 with the return value anyway.  But in the case
of clone, copy_thread will need the original value of r0 if the
CLONE_SETTLS flag was specified.

The first patch in this series fixes this issue for system calls by
pushing to the stack and extra copy of r0-r2 before invoking the
handler.  We discard this copy before restoring the userspace registers,
so it is not a problem if they are clobbered.

Exception handlers also receive the userspace register values in a
similar manner, and may hit the same problem.  The second patch removes
the do_fpu_error handler, which looks susceptible to this problem and
which, as far as I can tell, has not been used in some time.  The third
patch addresses other exception handlers.

This patch (of 3):

The userspace registers are stored at the top of the stack when the
syscall handler is invoked, which allows r0-r2 to act as parameters 5-7.
Parameters passed on the stack may be clobbered by the syscall handler.
The solution is to push an extra copy of the registers which might be
used as syscall parameters to the stack, so that the authoritative set
of saved register values does not get clobbered.

A few system call handlers are also updated to get the userspace
registers using current_pt_regs() instead of from the stack.

Signed-off-by: Bobby Bingham <koorogi@koorogi.info>
Cc: Paul Mundt <paul.mundt@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-03 16:20:52 -07:00
Thomas Gleixner 00d1a39e69 preempt: Make PREEMPT_ACTIVE generic
No point in having this bit defined by architecture.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20130917183629.090698799@linutronix.de
2013-11-13 20:21:47 +01:00
Al Viro 7147e21548 sh: switch to generic kernel_thread()/kernel_execve()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-10-22 22:31:01 -04:00
Al Viro 5e071e2b4b sh: Fix up TIF_NOTIFY_RESUME sans TIF_SIGPENDING handling.
As Al notes, we missed a TIF_NOTIFY_RESUME check which caused any
handlers without TIF_SIGPENDING also set to skip the notification:

	Looks like while it is in the relevant masks *and* checked in
	do_notify_resume() both on 32bit and 64bit variants since commit
	ab99c733ae ("sh: Make syscall tracer
	use tracehook notifiers, add TIF_NOTIFY_RESUME.") they are
	actually *not* reached without simulataneous SIGPENDING, since
	the actual glue in the callers had not been updated back then and
	still checks for _TIF_SIGPENDING alone when deciding whether to
	hit do_notify_resume() or not.

Reported-by: Nobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Tested-by: Nobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2012-09-18 17:04:37 +09:00
Paul Mundt 6330c04bb4 sh: Ensure IRQs are enabled across do_notify_resume().
do_notify_resume() can trigger the freezer via the try_to_freeze() path
(both explicitly through a redundant call in do_signal() or via
get_signal_to_deliver()). That IRQs were disabled across this callsite
became apparent with the might_sleep() introduction in try_to_freeze() by
Tejun in a0acae0e88, resulting in:

	BUG: sleeping function called from invalid context at include/linux/freezer.h:45
	in_atomic(): 0, irqs_disabled(): 1, pid: 819, name: ntpd
	no locks held by ntpd/819.
	Stack: (0x9c81be80 to 0x9c81c000)
	...

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2012-01-10 16:30:37 +09:00
Matt Fleming 142698282c sh: Correct the offset of the return address in ret_from_exception
The address that ret_from_exception and ret_from_irq will return to is
found in the stack slot for SPC, not PR. This error was causing the
DWARF unwinder to pick up the wrong return address on the stack and then
unwind using the unwind tables for the wrong function.

While I'm here I might as well add CFI annotations for the other
registers since they could be useful when unwinding.

Signed-off-by: Matt Fleming <matt@console-pimps.org>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2010-02-08 10:46:46 +09:00
Paul Mundt 56bfc42f6c sh: TS_RESTORE_SIGMASK conversion.
Replace TIF_RESTORE_SIGMASK with TS_RESTORE_SIGMASK and define our own
set_restore_sigmask() function.  This saves the costly SMP-safe set_bit
operation, which we do not need for the sigmask flag since TIF_SIGPENDING
always has to be set too.

Based on the x86 and powerpc change.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2009-10-14 16:05:42 +09:00
Paul Mundt 457b646189 sh: Fix a TRACE_IRQS_OFF typo.
The resume_userspace path had TRACE_IRQS_OFF written incorrectly and so
never handled the transition properly. This was fixed once before but
seems to have made it back in the tree. Fix it for good.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2009-10-14 15:50:28 +09:00
Stuart Menefy fea966f756 sh: Remove implicit sign extension from assembler immediates
The SH instruction set has several instructions which accept an 8 bit
immediate operand. For logical instructions this operand is zero extended,
for arithmetic instructions the operand is sign extended. After adding an
option to the assembler to check this, it was found that several pieces
of assembly code were assuming this behaviour, and in one case
getting it wrong.

So this patch explicitly sign extends any immediate operands, which makes
it obvious what is happening, and fixes the one case which got it wrong.

Signed-off-by: Stuart Menefy <stuart.menefy@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2009-08-24 17:09:53 +09:00
Matt Fleming f3a8308864 sh: Add a few missing irqflags tracing markers.
save_regs contains an SR modification without an irqflags annotation,
which resulted in a missing TRACE_IRQS_OFF in the interrupt exception
path on SH-3/SH4.

I've also moved the TRACE_IRQS_OFF/ON annotation when returning from the
interrupt to just before we call __restore_all. This seems like the most
logical place to put this because the annotation is for when we restore
the SR register so we should delay the annotation until as last as
possible.

We were also missing a TRACE_IRQS_OFF in resume_kernel when
CONFIG_PREEMPT is enabled.

The end result is that this fixes up the lockdep engine debugging support
with CONFIG_PREEMPT enabled on all SH-3/4 parts.

Signed-off-by: Matt Fleming <matt@console-pimps.org>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2009-08-18 11:35:09 +09:00
Matt Fleming cafb0ddac6 sh: Add CFI annotations for exception return.
Annotate various assembly code paths with CFI assembler directives so
that DWARF unwind info is available for the unwinder.

Signed-off-by: Matt Fleming <matt@console-pimps.org>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2009-08-14 02:02:07 +09:00
Matt Fleming 0b930489b8 sh: Setup the frame register in asm code
In order to use DWARF unwinder info the frame register has to contain a
valid value. Whilst GCC takes care of this for C code, we have to do it
ourselves for assembly.

Signed-off-by: Matt Fleming <matt@console-pimps.org>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2009-08-14 01:59:55 +09:00
Stuart Menefy fd78a76aef sh: Rework irqflags tracing to fix up CONFIG_PROVE_LOCKING.
This cleans up the irqflags tracing code quite a bit and ties it
in to various missing callsites that caused an imbalance when
CONFIG_PROVE_LOCKING was enabled.

Previously this was catching on:

 987 #ifdef CONFIG_PROVE_LOCKING
 988     DEBUG_LOCKS_WARN_ON(!p->hardirqs_enabled);
 989     DEBUG_LOCKS_WARN_ON(!p->softirqs_enabled);
 990 #endif
 991     retval = -EAGAIN;

with hardirqs being doubly enabled, and subsequently bailing out
with the following call trace:

	Call trace:
	[<88035224>] __lock_acquire+0x616/0x6a6
	[<88015a8c>] do_fork+0xf8/0x2b0
	[<880331ec>] trace_hardirqs_on_caller+0xd4/0x114
	[<88241074>] _spin_unlock_irq+0x20/0x64
	[<88035224>] __lock_acquire+0x616/0x6a6
	[<8800386c>] kernel_thread+0x48/0x70
	[<88024ecc>] ____call_usermodehelper+0x0/0x110
	[<88024ecc>] ____call_usermodehelper+0x0/0x110
	[<88003894>] kernel_thread_helper+0x0/0x14
	[<88024bac>] __call_usermodehelper+0x38/0x70
	[<88025dc0>] worker_thread+0x150/0x274
	[<88035b9c>] lock_release+0x0/0x198
	[<88024b74>] __call_usermodehelper+0x0/0x70
	[<88028cf0>] autoremove_wake_function+0x0/0x30
	[<88028bf2>] kthread+0x3e/0x70
	[<88025c70>] worker_thread+0x0/0x274
	[<8800389c>] kernel_thread_helper+0x8/0x14
	[<88028bb4>] kthread+0x0/0x70
	[<88003894>] kernel_thread_helper+0x0/0x14

Reported-by: Nobuhiro Iwamatsu <iwamatsu.nobuhiro@renesas.com>
Signed-off-by: Stuart Menefy <stuart.menefy@st.com>
Signed-off-by: Matt Fleming <matt@console-pimps.org>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2009-07-29 23:01:24 +09:00
Matt Fleming c652d780c9 sh: Add ftrace syscall tracing support
Now that I've added TIF_SYSCALL_FTRACE the thread flags do not fit into
a single byte any more. Code testing them now needs to be aware of the
upper and lower bytes.

Signed-off-by: Matt Fleming <matt@console-pimps.org>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2009-07-06 20:16:33 +09:00
Paul Mundt ab6e570ba3 sh: Generic kgdb stub support.
This migrates from the old bitrotted kgdb stub implementation and moves
to the generic stub. In the process support for SH-2/SH-2A is also added,
which the old stub never provided.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2008-12-22 18:44:04 +09:00
Matt Fleming fad57feba7 sh: dynamic ftrace support.
First cut at dynamic ftrace support.

Signed-off-by: Matt Fleming <mjf@gentoo.org>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2008-12-22 18:42:52 +09:00
Paul Mundt 694f94f263 sh: FTRACE renamed to FUNCTION_TRACER.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2008-10-31 16:20:36 +09:00
Paul Mundt 9d2b1f81dd sh: ftrace support.
This adds support for ftrace to SH. This only includes CONFIG_FTRACE,
and does not handle dynamic ftrace presently.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2008-09-21 16:43:45 +09:00
Carmelo Amoroso 323b8c410a sh: resume_kernel fix for kernel oops built with CONFIG_BKL_PREEMPT=y.
This patch fixes a problem within the SH implementation of resume_kernel code,
that implements in assembly the bulk of preempt_schedule_irq function without
taking care of the extra code needed to handle the BKL preemptible.

The patch basically consists of removing this asm code and calling the common
C implementation (see kernel/sched.c) as other archs do.

Another change is the missing 'cli' macro invocation at the beginning of
the resume_kernel.

Signed-off-by: Giuseppe Cavallaro <peppe.cavallaro@st.com>
Signed-off-by: Carmelo Amoroso <carmelo.amoroso@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2008-09-05 14:42:16 +09:00
Paul Mundt ab99c733ae sh: Make syscall tracer use tracehook notifiers, add TIF_NOTIFY_RESUME.
This follows the changes in commits:

7d6d637dac
4f72c4279e

on powerpc. Adding in TIF_NOTIFY_RESUME, and cleaning up the syscall
tracing to be more generic. This is an incremental step to turning
on tracehook, as well as unifying more of the ptrace and signal code
across the 32/64 split.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2008-08-02 04:39:33 +09:00
Paul Mundt cec3fd3e2a sh: Tidy up the _TIF work masks, and fix syscall trace bug on singlestep.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2008-08-02 04:39:32 +09:00
Stuart MENEFY 0b1689cfbb sh: Don't miss pending signals returning to user mode after signal processing
Without this patch, signals sent during architecture specific signal
handling (typically as a result of the user's stack being inaccessible)
are ignored.

This is the SH version of commit c3ff8ec31c
which was for the i386.

Signed-off-by: Stuart Menefy <stuart.menefy@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2008-07-28 18:10:37 +09:00
Paul Mundt 336f1d3268 sh: Fix up restorer in debug_trap exception return path.
There are a few different types of debug trap exceptions, though now
that they are all going through a special jump table, the restorer needs
to be unified as well.

Presently this is falling through the ret_from_fork path, which more or
less does the right thing on SH-3/4 whilst being completely unsuitable on
MMU-less targets.

Ultimately what we want here is a branch through the platform's
restore_all directly, without worrying about the retval being clobbered.
We can accomplish that through a branch to __restore_all directly, so
switch it so we come back from the jump table and branch to the restorer.

This fixes up a recursion in the nommu WARN_ON() path, as well as some
other userspace nastiness where said recursion caused serious stack
corruption.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2008-05-19 19:39:33 +09:00
Hideo Saito 561c2bccc7 sh: Fix up thread info pointer in syscall_badsys resume path.
Entry to resume_userspace expects r8 to contain current_thread_info,
which happens in all paths except for syscall_badsys, where r8 was
being inadvertently trampled. Reload it before the branch.

Signed-off-by: Hideo Saito <saito@densan.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2008-05-16 14:55:07 +09:00
Stuart Menefy 1efe4ce3ca sh: GUSA atomic rollback support.
This implements kernel-level atomic rollback built on top of gUSA,
as an alternative non-IRQ based atomicity method. This is generally
a faster method for platforms that are lacking the LL/SC pairs that
SH-4A and later use, and is only supportable on legacy cores.

Signed-off-by: Stuart Menefy <stuart.menefy@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2008-01-28 13:18:58 +09:00
Yuichi Nakamura 1322b9def9 sh: syscall audit support.
Support syscall auditing..

Signed-off-by: Yuichi Nakamura <ynakam@hitachisoft.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2008-01-28 13:18:57 +09:00
Paul Mundt 836624619b sh: Conditionalize gUSA support.
This conditionalizes gUSA support. gUSA is not supported on
SMP configurations, and it's not necessary there anyways due
to having other atomicity options (ie, movli.l/movco.l).

Anything implementing the LL/SC semantics (all SH-4A CPUs)
can switch to userspace atomicity implementations without
requiring gUSA. This is left default-enabled on all UP so
that glibc doesn't break.

Those that know what they are doing can disable this explicitly.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2007-09-28 16:04:49 +09:00
Stuart Menefy 9432f96803 sh: Clear UBC when not in use.
This takes care of tearing down the UBC so it's not inadvertently
left configured at the next context switch time. Failure to do
this results in spurious SIGTRAPs in certain debug sequences.

Signed-off-by: Stuart Menefy <stuart.menefy@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2007-03-05 14:13:25 +09:00
Paul Mundt f413d0d9fa sh: Use a jump call table for debug trap handlers.
This rips out most of the needlessly complicated sh_bios and kgdb
trap handling, and forces it all through a common fast dispatch path.
As more debug traps are inserted, it's important to keep them in sync
for all of the parts, not just SH-3/4.

As the SH-2 parts are unable to do traps in the >= 0x40 range, we
restrict the debug traps to the 0x30-0x3f range on all parts, and
also bump the kgdb breakpoint trap down in to this range (from 0xff
to 0x3c) so it's possible to use for nommu.

Optionally, this table can be padded out to catch spurious traps for
SH-3/4, but we don't do that yet..

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2007-02-13 10:54:43 +09:00
Paul Mundt 1dc417d039 sh: Fixup sh_bios() trap handling.
This was inadvertently broken when the entry.S code split up,
restore the missing branch and get subsequent traps working
under debug again. This manifested itself as a lockup when
attempting to reload the VBR base.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2006-12-12 08:42:09 +09:00
Paul Mundt afbfb52e47 sh: stacktrace/lockdep/irqflags tracing support.
Wire up all of the essentials for lockdep..

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2006-12-06 10:45:40 +09:00
Stuart Menefy e0969e0c9b sh: Fix syscall tracing ordering.
The implementation of system call tracing in the kernel has a
couple of ordering problems:

 - the validity of the system call number is checked before
   calling out to system call tracing code, and should be
   done after

 - the system call number used when tracing is the one the
   system call was invoked with, while the system call tracing
   code can legitimatly change the call number (for example
   strace permutes fork into clone)

This patch fixes both of these problems, and also reoders the
code slightly to make the direct path through the code the
common case.

Signed-off-by: Stuart Menefy <stuart.menefy@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2006-12-06 10:45:38 +09:00
Yoshinori Sato de39840646 sh: Exception vector rework and SH-2/SH-2A support.
This splits out common bits from the existing exception handler for
use between SH-2/SH-2A and SH-3/4, and adds support for the SH-2/2A
exceptions.

Signed-off-by: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2006-12-06 10:45:36 +09:00