Presently there's no SHmedia support plugged in for the dwarf unwinder.
While it's trivial to provide an SHmedia version of dwarf_read_arch_reg(),
the general sh64 case is more complicated in that the TLB miss handler
uses a locked down set of registers for optimization (including the frame
pointer) which we need for the unwind table generation.
While freeing up the frame pointer for use in the TLB miss handler is
reasonably straightforward, it's still more trouble than it's worth, so
we simply restrict the unwinder to 32-bit for now.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Now when the sh-sci driver can do early serial output,
get rid of the old duplicated code. This patch is V2 and
removes support for "earlyprintk=serial" together with
the following kconfig options:
CONFIG_EARLY_SCIF_CONSOLE
CONFIG_EARLY_SCIF_CONSOLE_PORT
CONFIG_EARLY_PRINTK
With this patch applied "earlyprintk=" support is always
built-in the SuperH kernel. For this to work the serial
driver must have early platform support and in the case
of sh-sci the serial console needs to be enabled:
CONFIG_SERIAL_SH_SCI_CONSOLE=y
So after enabling the SuperH SCI console kconfig option
you also need to point out port using the kernel command
line: "earlyprintk=sh-sci.N[,baudrate][,keep]"
Remember that clocks may be disabled by the boot loader
so you may have to do some board specific static clock
setup before earlyprintk will work on your platform.
Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This is a first cut at a generic DWARF unwinder for the kernel. It's
still lacking DWARF64 support and the DWARF expression support hasn't
been tested very well but it is generating proper stacktraces on SH for
WARN_ON() and NULL dereferences.
Signed-off-by: Matt Fleming <matt@console-pimps.org>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This adds early printk support for SH770x (tested on SH7709 based hp6xx).
Signed-off-by: Rafael Ignacio Zurita <rizurita@yahoo.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
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>
STACK_DEBUG ties in to mcount in order to do function-granular stack
overflow checks as opposed to lazily checking from IRQ context. As the
default is nohz, the frequency of overflow checking is too irregular to
catch much useful information, and so the mcount approach employed by
sparc64 is adopted instead.
This kills off the old check entirely from the do_IRQ() path and now
adopts CONFIG_MCOUNT instead.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This adds a general CONFIG_MCOUNT in order to permit mcount generation
without ftrace support. This is primarily for allowing platforms to
enable aggressive stack overflow checking without having to enable ftrace
support. Based on the sparc64 implementation.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Enable kernel stack checking code in both the dynamic ftrace and mcount
code paths. Check the stack to see if it's overflowing and make sure
that the stack pointer contains an address that's either in init_stack
or after the bss.
Signed-off-by: Matt Fleming <matt@console-pimps.org>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
There is no real reason to use this anymore, as the build system
generally knows what it is doing with regards to cflags mangling.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This patch moves the SH4 case of EARLY_SCIF_CONSOLE_PORT
so the SH7785 default value gets used. Without this patch
the value for SH7785 is set to 0xffe80000.
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
There still seems to be some stack corruption to sort out here, so flag
this as BROKEN until this issue is sorted out.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
We don't really want this enabled by default, but it is still quite
useful for debugging. So, make it conditional and leave it off by
default.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This enables the same functionality that sh64 has for sh32. When running
on simulated hardware or via remote memory via the debug interface,
memory is gauranteed to be zero on boot already, and skipping the zeroing
of BSS has measurable boot time benefits.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
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>
This converts the sh64 /proc/asids entry to debugfs and enables it for
all SH parts that have debugfs enabled.
On MMU systems this can be used to determine which processes are using
which ASIDs which in turn can be used for finer grained cache tag
analysis.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This combination triggers a divide by zero in kernel/fork.c when
calculating the initial max_threads value:
max_threads = mempages / (8 * THREAD_SIZE / PAGE_SIZE);
Simply disable 4K stacks on 64kB PAGE_SIZE to work around this,
as it's not a terribly useful combination to begin with.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
