Add a dt-bindings symlink to get DT include files, as on other
architectures. See c58299a ("kbuild: create an "include chroot" for DT
bindings") for the details.
Signed-off-by: Rabin Vincent <rabin@rab.in>
Signed-off-by: Jesper Nilsson <jespern@axis.com>
Within one C file, current gcc can optimize the global static variables
according to the C code, but it will skip assembly code -- it will pass
them to gas directly.
if the static variable is used between C code and assembly code in one C
file (e.g. is_dyn_brkp in kgdb.c), it needs '__used' to let gcc know it
should be still used, or gcc may remove it for optimization.
The related error in this case:
LD init/built-in.o
arch/cris/arch-v10/kernel/built-in.o: In function `kgdb_handle_breakpoint':
(.text+0x2aca): undefined reference to `is_dyn_brkp'
arch/cris/arch-v10/kernel/built-in.o: In function `is_static':
kgdb.c:(.text+0x2ada): undefined reference to `is_dyn_brkp'
Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com>
Signed-off-by: Jesper Nilsson <jespern@axis.com>
For arch-v10, there is no DTP0 register, and at present, assembler know
BAR, so use BAR instead of DTP0, the related error (with allmodconfig):
CC arch/cris/arch-v10/kernel/kgdb.o
{standard input}: Assembler messages:
{standard input}:6: Error: Illegal operands
{standard input}:6: Error: Illegal operands
Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com>
Acked-by: Hans-Peter Nilsson <hp@axis.com>
Signed-off-by: Jesper Nilsson <jespern@axis.com>
There are kernel native helpers to convert hex ascii to the binary format:
hex_to_bin() and hex2bin(). Thus, no need to reimplement them customly.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Jesper Nilsson <jespern@axis.com>
Pull strscpy string copy function implementation from Chris Metcalf.
Chris sent this during the merge window, but I waffled back and forth on
the pull request, which is why it's going in only now.
The new "strscpy()" function is definitely easier to use and more secure
than either strncpy() or strlcpy(), both of which are horrible nasty
interfaces that have serious and irredeemable problems.
strncpy() has a useless return value, and doesn't NUL-terminate an
overlong result. To make matters worse, it pads a short result with
zeroes, which is a performance disaster if you have big buffers.
strlcpy(), by contrast, is a mis-designed "fix" for strlcpy(), lacking
the insane NUL padding, but having a differently broken return value
which returns the original length of the source string. Which means
that it will read characters past the count from the source buffer, and
you have to trust the source to be properly terminated. It also makes
error handling fragile, since the test for overflow is unnecessarily
subtle.
strscpy() avoids both these problems, guaranteeing the NUL termination
(but not excessive padding) if the destination size wasn't zero, and
making the overflow condition very obvious by returning -E2BIG. It also
doesn't read past the size of the source, and can thus be used for
untrusted source data too.
So why did I waffle about this for so long?
Every time we introduce a new-and-improved interface, people start doing
these interminable series of trivial conversion patches.
And every time that happens, somebody does some silly mistake, and the
conversion patch to the improved interface actually makes things worse.
Because the patch is mindnumbing and trivial, nobody has the attention
span to look at it carefully, and it's usually done over large swatches
of source code which means that not every conversion gets tested.
So I'm pulling the strscpy() support because it *is* a better interface.
But I will refuse to pull mindless conversion patches. Use this in
places where it makes sense, but don't do trivial patches to fix things
that aren't actually known to be broken.
* 'strscpy' of git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile:
tile: use global strscpy() rather than private copy
string: provide strscpy()
Make asm/word-at-a-time.h available on all architectures
With lockdep support implemented on CRISv32, we get the following splat.
switch_mm() can be called both from the scheduler() (with interrupts
disabled) and from flush_old_exec (via activate_mm()), with interrupts
enabled. Fix it by disabling interrupts in activate_mm(), similar to
powerpc and hexagon.
t======================================================
[ INFO: HARDIRQ-safe -> HARDIRQ-unsafe lock order detected ]
3.19.0-08802-g20bc9f1-dirty #323 Not tainted
------------------------------------------------------
init/1 [HC0[0]:SC0[0]:HE0:SE1] is trying to acquire:
(mmu_context_lock){+.+...}, at: [<c0009290>] switch_mm+0x22/0xc6
and this task is already holding:
(&rq->lock){-.-.-.}, at: [<c01a0756>] __schedule+0x5e/0x648
which would create a new lock dependency:
(&rq->lock){-.-.-.} -> (mmu_context_lock){+.+...}
but this new dependency connects a HARDIRQ-irq-safe lock:
(&rq->lock){-.-.-.}
... which became HARDIRQ-irq-safe at:
[<c002b03c>] scheduler_tick+0x28/0x5e
[<c0007c6c>] timer_interrupt+0x4e/0x6a
[<c0043ac4>] handle_irq_event_percpu+0x54/0x13c
[<c004343c>] generic_handle_irq+0x2a/0x36
to a HARDIRQ-irq-unsafe lock:
(mmu_context_lock){+.+...}
... which became HARDIRQ-irq-unsafe at:
... [<c0039e60>] __lock_acquire+0x8f8/0x1d9c
[<c0009290>] switch_mm+0x22/0xc6
[<c009c260>] flush_old_exec+0x500/0x5d4
[<c00da4c6>] load_elf_phdrs+0x7a/0x84
[<c00dbdb0>] load_elf_binary+0x21c/0x13b4
[<c009cdb6>] do_execve+0x22/0x2c
[<c001dcf2>] ____call_usermodehelper+0x0/0x154
[<c000581e>] ret_from_kernel_thread+0xe/0x14
other info that might help us debug this:
Possible interrupt unsafe locking scenario:
CPU0 CPU1
---- ----
lock(mmu_context_lock);
local_irq_disable();
lock(&rq->lock);
lock(mmu_context_lock);
<Interrupt>
lock(&rq->lock);
*** DEADLOCK ***
1 lock held by init/1:
#0: (&rq->lock){-.-.-.}, at: [<c01a0756>] __schedule+0x5e/0x648
Call Trace:
[<c019fe9e>] printk+0x0/0x4e
[<c00368f8>] print_shortest_lock_dependencies+0x0/0x15c
[<c0048628>] print_stack_trace+0x0/0x88
[<c0038912>] __lock_is_held+0x3e/0x5e
[<c003b894>] lock_acquire+0x8a/0xcc
[<c01a50c4>] _raw_spin_lock+0x44/0x7a
[<c0009290>] switch_mm+0x22/0xc6
[<c01a06f8>] __schedule+0x0/0x648
[<c01a0d76>] schedule+0x36/0x7c
[<c0037d04>] trace_hardirqs_on+0x0/0x1e
[<c0004e18>] do_work_pending+0x30/0xd4
[<c000591a>] _work_pending+0xe/0x12
Signed-off-by: Rabin Vincent <rabin@rab.in>
Signed-off-by: Jesper Nilsson <jesper.nilsson@axis.com>
Now that we have stack tracing and irq flags tracing support,
we can also enable lockdep support
Signed-off-by: Rabin Vincent <rabin@rab.in>
Signed-off-by: Jesper Nilsson <jesper.nilsson@axis.com>
Add stacktrace support, which is required for lockdep and tracing. The
stack tracing simply looks at all kernel text symbols found on the
stack, similar to the trap stack dumping code, which can also be
converted to use this.
Signed-off-by: Rabin Vincent <rabin@rab.in>
Signed-off-by: Jesper Nilsson <jesper.nilsson@axis.com>
Use a call to local_irq_enable() instead of incline asm so that the
irqsoff latency tracer knows that interrupts are enabled here.
Signed-off-by: Rabin Vincent <rabin@rab.in>
Signed-off-by: Jesper Nilsson <jesper.nilsson@axis.com>
Add support irqflags tracing, which is required for things like lockdep
and ftrace.
Signed-off-by: Rabin Vincent <rabin@rab.in>
Signed-off-by: Jesper Nilsson <jesper.nilsson@axis.com>
CRIS userspace (uClibc for one) expects asm/elf.h to be exported but
this header appears to have gone missing at some point. Move it to
uapi/ and export it.
Signed-off-by: Rabin Vincent <rabin@rab.in>
Signed-off-by: Jesper Nilsson <jesper.nilsson@axis.com>
We're going to export asm/elf.h; remove its dependencies on the
non-exported asm/user.h and the unused asm/system.h include.
Signed-off-by: Rabin Vincent <rabin@rab.in>
Signed-off-by: Jesper Nilsson <jesper.nilsson@axis.com>
The exported ptrace.h header on CRIS references an "arch" directory
which does not exist. Fix this by having the variants in the same
directory and including them conditionally, similar to other
architectures.
Signed-off-by: Rabin Vincent <rabin@rab.in>
Signed-off-by: Jesper Nilsson <jesper.nilsson@axis.com>
Rabin Vincent
Chen Gang
Andy Shevchenko
Linus Torvalds
Jesper Nilsson