linux-stable.git/arch/nios2/kernel/entry.S, branch linux-4.9.y Linux kernel stable tree nios2: add force_successful_syscall_return() 2022-08-25T09:09:30+00:00 Al Viro viro@zeniv.linux.org.uk 2022-08-08T15:09:45+00:00 53d6075164592d2af1b5078e4924ddf2b04b3e78 commit fd0c153daad135d0ec1a53c5dbe6936a724d6ae1 upstream. If we use the ancient SysV syscall ABI, we'd better have tell the kernel how to claim that a negative return value is a success. Use ->orig_r2 for that - it's inaccessible via ptrace, so it's a fair game for changes and it's normally[*] non-negative on return from syscall. Set to -1; syscall is not going to be restart-worthy by definition, so we won't interfere with that use either. [*] the only exception is rt_sigreturn(), where we skip the entire messing with r1/r2 anyway. Fixes: 82ed08dd1b0e ("nios2: Exception handling") Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Dinh Nguyen <dinguyen@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit fd0c153daad135d0ec1a53c5dbe6936a724d6ae1 upstream.

If we use the ancient SysV syscall ABI, we'd better have tell the
kernel how to claim that a negative return value is a success.
Use ->orig_r2 for that - it's inaccessible via ptrace, so it's
a fair game for changes and it's normally[*] non-negative on return
from syscall.  Set to -1; syscall is not going to be restart-worthy
by definition, so we won't interfere with that use either.

[*] the only exception is rt_sigreturn(), where we skip the entire
messing with r1/r2 anyway.

Fixes: 82ed08dd1b0e ("nios2: Exception handling")
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Dinh Nguyen <dinguyen@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
nios2: traced syscall does need to check the syscall number 2022-08-25T09:09:29+00:00 Al Viro viro@zeniv.linux.org.uk 2022-08-08T15:07:21+00:00 60cd5c1a0667294acac87728086f0b574f3ae5cc commit 25ba820ef36bdbaf9884adeac69b6e1821a7df76 upstream. all checks done before letting the tracer modify the register state are worthless... Fixes: 82ed08dd1b0e ("nios2: Exception handling") Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Dinh Nguyen <dinguyen@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 25ba820ef36bdbaf9884adeac69b6e1821a7df76 upstream.

all checks done before letting the tracer modify the register
state are worthless...

Fixes: 82ed08dd1b0e ("nios2: Exception handling")
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Dinh Nguyen <dinguyen@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
nios2: don't leave NULLs in sys_call_table[] 2022-08-25T09:09:29+00:00 Al Viro viro@zeniv.linux.org.uk 2022-08-08T15:06:46+00:00 8c7739f57084da2075f09de820b99da7e606dc8d commit 45ec746c65097c25e77d24eae8fee0def5b6cc5d upstream. fill the gaps in there with sys_ni_syscall, as everyone does... Fixes: 82ed08dd1b0e ("nios2: Exception handling") Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Dinh Nguyen <dinguyen@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 45ec746c65097c25e77d24eae8fee0def5b6cc5d upstream.

fill the gaps in there with sys_ni_syscall, as everyone does...

Fixes: 82ed08dd1b0e ("nios2: Exception handling")
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Dinh Nguyen <dinguyen@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
nios2: page fault et.al. are *not* restartable syscalls... 2022-08-25T09:09:29+00:00 Al Viro viro@zeniv.linux.org.uk 2022-08-08T15:06:04+00:00 c0710869c3cead7b404284bc2d9b11c570864973 commit 8535c239ac674f7ead0f2652932d35c52c4123b2 upstream. make sure that ->orig_r2 is negative for everything except the syscalls. Fixes: 82ed08dd1b0e ("nios2: Exception handling") Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Dinh Nguyen <dinguyen@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 8535c239ac674f7ead0f2652932d35c52c4123b2 upstream.

make sure that ->orig_r2 is negative for everything except
the syscalls.

Fixes: 82ed08dd1b0e ("nios2: Exception handling")
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Dinh Nguyen <dinguyen@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
nios2: rework trap handler 2015-04-20T03:11:14+00:00 Ley Foon Tan lftan@altera.com 2015-04-16T07:19:01+00:00 baa54ab93c2e1ced7e54f9c021fe102c0d39c090 Redefine trap handler as below: 0 N/A reserved for system calls 1 SIGUSR1 user-defined signal 1 2 SIGUSR2 user-defined signal 2 3 SIGILL illegal instruction 4..29 reserved (but implemented to raise SIGILL instead of being undefined) 30 SIGTRAP KGDB 31 SIGTRAP trace/breakpoint trap Signed-off-by: Ley Foon Tan <lftan@altera.com> 
Redefine trap handler as below:

 0  N/A        reserved for system calls
 1  SIGUSR1    user-defined signal 1
 2  SIGUSR2    user-defined signal 2
 3  SIGILL     illegal instruction
 4..29         reserved (but implemented to raise SIGILL instead of being undefined)
30  SIGTRAP    KGDB
31  SIGTRAP    trace/breakpoint trap

Signed-off-by: Ley Foon Tan <lftan@altera.com>
nios2: fix cache coherency issue when debug with gdb 2015-04-10T03:10:08+00:00 Ley Foon Tan lftan@altera.com 2015-04-10T03:10:08+00:00 4a89c3088ff61aa24754e9cd6dc665cc719f7efe Remove the end address checking for flushda function. We need to flush each address line for flushda instruction, from start to end address. This is because flushda instruction only flush the cache if tag and line fields are matched. Change to use ldwio instruction (bypass cache) to load the instruction that causing trap. Our interest is the actual instruction that executed by the processor, this should be uncached. Note, EA address might be an userspace cached address. Signed-off-by: Ley Foon Tan <lftan@altera.com> 
Remove the end address checking for flushda function. We need to flush
each address line for flushda instruction, from start to end address.
This is because flushda instruction only flush the cache if tag and line
fields are matched.

Change to use ldwio instruction (bypass cache) to load the instruction
that causing trap. Our interest is the actual instruction that executed
by the processor, this should be uncached.
Note, EA address might be an userspace cached address.


Signed-off-by: Ley Foon Tan <lftan@altera.com>
nios2: add kgdb support 2015-02-16T11:26:43+00:00 Ley Foon Tan lftan@altera.com 2015-02-16T11:26:43+00:00 d16d2be111a61baf3a4696f07bfc7a8e36697cec Signed-off-by: Ley Foon Tan <lftan@altera.com> 
Signed-off-by: Ley Foon Tan <lftan@altera.com>
nios2: Use preempt_schedule_irq 2014-12-31T03:04:58+00:00 Tobias Klauser tklauser@distanz.ch 2014-12-31T02:53:11+00:00 1b0f44923e186b2f9383b3260f6b5fbfc77b9e4a Follow aa0d53260596 ("ia64: Use preempt_schedule_irq") and use preempt_schedule_irq instead of enabling/disabling interrupts and messing around with PREEMPT_ACTIVE in the nios2 low-level preemption code ourselves. Also get rid of the now needless re-check for TIF_NEED_RESCHED, preempt_schedule_irq will already take care of rescheduling. This also fixes the following build error when building with CONFIG_PREEMPT: arch/nios2/kernel/built-in.o: In function `need_resched': arch/nios2/kernel/entry.S:374: undefined reference to `PREEMPT_ACTIVE' Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Tobias Klauser <tklauser@distanz.ch> Acked-by: Ley Foon Tan <lftan@altera.com> 
Follow aa0d53260596 ("ia64: Use preempt_schedule_irq") and use
preempt_schedule_irq instead of enabling/disabling interrupts and
messing around with PREEMPT_ACTIVE in the nios2 low-level preemption
code ourselves. Also get rid of the now needless re-check for
TIF_NEED_RESCHED, preempt_schedule_irq will already take care of
rescheduling.

This also fixes the following build error when building with
CONFIG_PREEMPT:

arch/nios2/kernel/built-in.o: In function `need_resched':
arch/nios2/kernel/entry.S:374: undefined reference to `PREEMPT_ACTIVE'

Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Acked-by: Ley Foon Tan <lftan@altera.com>
nios2: Exception handling 2014-12-08T04:55:50+00:00 Ley Foon Tan lftan@altera.com 2014-11-06T07:19:38+00:00 82ed08dd1b0e0e0728f9188f66795c49dffe437d This patch contains the exception entry code (kernel/entry.S) and misaligned exception. Signed-off-by: Ley Foon Tan <lftan@altera.com> 
This patch contains the exception entry code (kernel/entry.S) and
misaligned exception.

Signed-off-by: Ley Foon Tan <lftan@altera.com>