Replace 'the the' with 'like the' in the comment.
Replace 'an' with 'a'.

Signed-off-by: Slark Xiao <slark_xiao@163.com>
Signed-off-by: Michal Simek <michal.simek@amd.com>
Link: https://lore.kernel.org/r/20220721071520.48384-1-slark_xiao@163.com

There is a need to disable VM before jump to zero reset vector.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Reviewed-by: Stefan Asserhall <stefan.asserhall@xilinx.com>

CONFIG_PREEMPTION is selected by CONFIG_PREEMPT and by CONFIG_PREEMPT_RT.
Both PREEMPT and PREEMPT_RT require the same functionality which today
depends on CONFIG_PREEMPT.

Switch the entry code over to use CONFIG_PREEMPTION.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20191015191821.11479-12-bigeasy@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>

Since the enabling and disabling of IRQs within preempt_schedule_irq()
is contained in a need_resched() loop, we don't need the outer arch
code loop.

Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Cc: Michal Simek <monstr@monstr.eu>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>

The issue was that the service routine was sometimes
returning with the wrong flags set in the MSR.

In this case, EIP bit was set while returning to User Mode
which is an illegal combination since exceptions are always
handled in privileged mode.

In order for MicroBlaze to take an interrupt, the MSR must have IE=1,
BIP=0 and EIP=0.

Signed-off-by: Stefan Asserhall <stefana@xilinx.com>
Signed-off-by: Goran Bilski <goran@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>

Separate general purpose register restoring from MSR handling.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>

This patch fixes two bugs in the Microblaze syscall trap handler when an invalid
syscall ID is used.

First, the range check on line 351 only checks for syscall IDs greater than
__NR_syscalls. A negative syscall ID (either passed to `syscall()` or as returned
by `do_syscall_trace_enter()` on error) will still satisfy this test and cause
the Linux kernel to access an invalid memory location and cause a kernel oops.
This has been fixed by also checking for r12 < 0.

Secondly, the current error recovery at line 378 returns using the wrong register
(r15 instead of r14) and does not restore the previous stack state. This has been
fixed by invoking `ret_from_trap` on error, setting r3 to `-ENOSYS`, similar to
what would happen when calling a valid syscall.

Signed-off-by: Jamie Garside <jamie.garside@york.ac.uk>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>

No function change.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>

Better not to break block which do work together.

Signed-off-by: Michal Simek <monstr@monstr.eu>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

We need to keep building sigframes until no pending signals remain.
Wrap do_notify_resume() calls into loops; do _not_ allow syscall
restart logics to trigger after the first iteration.

Incidentally, comments about pending signals that should (somehow)
be in r18 are pure BS.  Doesn't work that way and cannot work that
way, sorry...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>