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2018-12-28sh: kernel: convert to SPDX identifiersKuninori Morimoto1-6/+2
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>
2018-04-12sh: fix debug trap failure to process signals before return to userRich Felker1-1/+1
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>
2016-03-17sh: provide unified syscall trap compatible with all SH modelsRich Felker1-6/+15
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>
2014-04-03sh: push extra copy of r0-r2 for syscall parametersBobby Bingham1-4/+11
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>
2013-11-13preempt: Make PREEMPT_ACTIVE genericThomas Gleixner1-4/+2
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
2012-10-22sh: switch to generic kernel_thread()/kernel_execve()Al Viro1-0/+13
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-09-18sh: Fix up TIF_NOTIFY_RESUME sans TIF_SIGPENDING handling.Al Viro1-1/+1
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 ab99c733ae73cce31f2a2434f7099564e5a73d95 ("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>
2012-01-10sh: Ensure IRQs are enabled across do_notify_resume().Paul Mundt1-0/+1
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 a0acae0e886d44bd5ce6d2f173c1ace0fcf0d9f6, 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>
2010-02-08sh: Correct the offset of the return address in ret_from_exceptionMatt Fleming1-1/+7
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>
2009-10-14sh: TS_RESTORE_SIGMASK conversion.Paul Mundt1-1/+1
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>
2009-10-14sh: Fix a TRACE_IRQS_OFF typo.Paul Mundt1-1/+1
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>
2009-08-24sh: Remove implicit sign extension from assembler immediatesStuart Menefy1-2/+3
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>
2009-08-18sh: Add a few missing irqflags tracing markers.Matt Fleming1-11/+16
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>
2009-08-14sh: Add CFI annotations for exception return.Matt Fleming1-0/+7
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>
2009-08-14sh: Setup the frame register in asm codeMatt Fleming1-0/+1
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>
2009-07-29sh: Rework irqflags tracing to fix up CONFIG_PROVE_LOCKING.Stuart Menefy1-47/+16
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>
2009-07-06sh: Add ftrace syscall tracing supportMatt Fleming1-5/+13
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>
2008-12-22sh: Generic kgdb stub support.Paul Mundt1-3/+7
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>
2008-12-22sh: dynamic ftrace support.Matt Fleming1-44/+0
First cut at dynamic ftrace support. Signed-off-by: Matt Fleming <mjf@gentoo.org> Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2008-10-31sh: FTRACE renamed to FUNCTION_TRACER.Paul Mundt1-2/+2
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2008-09-21sh: ftrace support.Paul Mundt1-0/+44
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>
2008-09-05sh: resume_kernel fix for kernel oops built with CONFIG_BKL_PREEMPT=y.Carmelo Amoroso1-24/+3
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>
2008-08-02sh: Make syscall tracer use tracehook notifiers, add TIF_NOTIFY_RESUME.Paul Mundt1-7/+5
This follows the changes in commits: 7d6d637dac2050f30a1b57b0a3dc5de4a10616ba 4f72c4279eab1e5f3ed1ac4e55d4527617582392 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>
2008-08-02sh: Tidy up the _TIF work masks, and fix syscall trace bug on singlestep.Paul Mundt1-2/+2
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2008-07-28sh: Don't miss pending signals returning to user mode after signal processingStuart MENEFY1-1/+1
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 c3ff8ec31c1249d268cd11390649768a12bec1b9 which was for the i386. Signed-off-by: Stuart Menefy <stuart.menefy@st.com> Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2008-05-19sh: Fix up restorer in debug_trap exception return path.Paul Mundt1-6/+5
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>
2008-05-16sh: Fix up thread info pointer in syscall_badsys resume path.Hideo Saito1-0/+1
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>
2008-01-28sh: GUSA atomic rollback support.Stuart Menefy1-19/+0
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>
2008-01-28sh: syscall audit support.Yuichi Nakamura1-2/+6
Support syscall auditing.. Signed-off-by: Yuichi Nakamura <ynakam@hitachisoft.jp> Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2007-09-28sh: Conditionalize gUSA support.Paul Mundt1-1/+1
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>
2007-03-05sh: Clear UBC when not in use.Stuart Menefy1-1/+1
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>
2007-02-13sh: Use a jump call table for debug trap handlers.Paul Mundt1-76/+43
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>
2006-12-12sh: Fixup sh_bios() trap handling.Paul Mundt1-2/+13
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>
2006-12-06sh: stacktrace/lockdep/irqflags tracing support.Paul Mundt1-1/+63
Wire up all of the essentials for lockdep.. Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2006-12-06sh: Fix syscall tracing ordering.Stuart Menefy1-23/+22
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>
2006-12-06sh: Exception vector rework and SH-2/SH-2A support.Yoshinori Sato1-0/+372
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>