For debuggers to take advantage of the hw-breakpoint framework in the kernel,
it is necessary to expose the API calls via a ptrace interface.
This patch exposes the hardware breakpoints framework as a collection of
virtual registers, accesible using PTRACE_SETHBPREGS and PTRACE_GETHBPREGS
requests. The breakpoints are stored in the debug_info struct of the running
thread.
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: S. Karthikeyan <informkarthik@gmail.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This patch enables the HAVE_REGS_AND_STACK_ACCESS_API option
for ARM which is required by the kprobe events tracer. Code based
on the PowerPC port.
Cc: Jean Pihet <jpihet@mvista.com>
Tested-by: Jamie Iles <jamie.iles@picochip.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Use the generic ptrace_resume code for PTRACE_SYSCALL, PTRACE_CONT,
PTRACE_KILL and PTRACE_SINGLESTEP. This implies defining
arch_has_single_step in <asm/ptrace.h> and implementing the
user_enable_single_step and user_disable_single_step functions, which also
causes the breakpoint information to be cleared on fork, which could be
considered a bug fix.
Also the TIF_SYSCALL_TRACE thread flag is now cleared on PTRACE_KILL which
it previously wasn't and the single stepping disable only happens if the
tracee process isn't a zombie yet, which is consistent with all
architectures using the modern ptrace code.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Roland McGrath <roland@redhat.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Make registers unsigned for kernel space. This is important for
example in the perf events where the PC is stored into a u64. We
don't want it sign extended so make the regs unsigned to prevent
casts throughout the kernel.
Signed-off-by: Jamie Iles <jamie.iles@picochip.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The patch below adds ARM ptrace functions to get the process load address.
This is required for useful userspace debugging on mmuless systems. These
values are obtained by reading magic offsets with PTRACE_PEEKUSR, as on other
nommu targets. I picked arbitrary large values for the offsets.
Signed-off-by: Paul Brook <paul@codesourcery.com>
Starting with ARMv6, the CPUs support the BE-8 variant of big-endian
(byte-invariant). This patch adds the core support:
- setting of the BE-8 mode via the CPSR.E register for both kernel and
user threads
- big-endian page table walking
- REV used to rotate instructions read from memory during fault
processing as they are still little-endian format
- Kconfig and Makefile support for BE-8. The --be8 option must be passed
to the final linking stage to convert the instructions to
little-endian
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
If a process is interrupted during an If-Then block and a signal is
invoked, the ITSTATE bits must be cleared otherwise the handler would
not run correctly.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Joseph S. Myers <joseph@codesourcery.com>
This patch adds ptrace support for setting and getting the VFP registers
using PTRACE_SETVFPREGS and PTRACE_GETVFPREGS. The user_vfp structure
defined in asm/user.h contains 32 double registers (to cover VFPv3 and
Neon hardware) and the FPSCR register.
Cc: Paul Brook <paul@codesourcery.com>
Cc: Daniel Jacobowitz <dan@codesourcery.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
pc_pointer() was a function to mask the PC for 26-bit ARMs, which
we no longer support. Remove it.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Move platform independent header files to arch/arm/include/asm, leaving
those in asm/arch* and asm/plat* alone.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This patch contains the following cleanups for the asm/ptrace.h
userspace headers:
- include/asm-generic/Kbuild.asm already lists ptrace.h, remove
the superfluous listings in the Kbuild files of the following
architectures:
- cris
- frv
- powerpc
- x86
- don't expose function prototypes and macros to userspace:
- arm
- blackfin
- cris
- mn10300
- parisc
- remove #ifdef CONFIG_'s around #define's:
- blackfin
- m68knommu
- sh: AFAIK __SH5__ should work in both kernel and userspace,
no need to leak CONFIG_SUPERH64 to userspace
- xtensa: cosmetical change to remove empty
#ifndef __ASSEMBLY__ #else #endif
from the userspace headers
Not changed by this patch is the fact that the following architectures
have a different struct pt_regs depending on CONFIG_ variables:
- h8300
- m68knommu
- mips
This does not work in userspace.
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Cc: <linux-arch@vger.kernel.org>
Cc: Roland McGrath <roland@redhat.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Acked-by: Greg Ungerer <gerg@uclinux.org>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Acked-by: Grant Grundler <grundler@parisc-linux.org>
Acked-by: Jesper Nilsson <jesper.nilsson@axis.com>
Acked-by: Chris Zankel <chris@zankel.net>
Acked-by: David Howells <dhowells@redhat.com>
Acked-by: Paul Mackerras <paulus@samba.org>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When running Linux in non-secure mode (on ARM1176 for example),
depending on the CP15 secure configuration register, the CPSR.F bit
(6) might only be modified from the secure mode. However, the
valid_user_regs() function checks for this bit being cleared. With
commit a6c61e9d, a SIGSEGV is forced in handle_signal() if the user
registers are not considered valid.
The patch also ensures that the CPSR.A bit is cleared and the USR mode
is set if the CPU does not support the 26bit user mode.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The ARM show_regs() tombstone only partially decodes which ARM ISA was
executing at the time a fault occurred displaying either "(T)" for the
Thumb case or nothing at all for other cases. This patch therefore
explicitly identifies which state the processor is in at the time of
a fault: ARM, Thumb, Jazelle or JazelleEE.
Signed-off-by: George G. Davis <gdavis@mvista.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Add the kernel release and version information to the output of
show_regs/oops. Add the CPU PSR register. Avoid using printk
to output partial lines; always output a complete line.
Re-combine the "Control" and "Table + DAC" lines after nommu
separated them; we don't want to waste vertical screen space
needlessly.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Patch from Lennert Buytenhek
This patch makes it possible to get/set a task's Crunch state via
the ptrace(2) system call.
Signed-off-by: Lennert Buytenhek <buytenh@wantstofly.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Patch from Nicolas Pitre
This is needed by strace to properly handle the tracing of some system
calls. It could be useful for other applications as well.
Based on an earlier patch from Daniel Jacobowitz.
Signed-off-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: Daniel Jacobowitz <dan@debian.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Patch from Nicolas Pitre
The ARM EABI says that the stack pointer has to be 64-bit aligned for
reasons already mentioned in patch #3101 when calling C functions.
We therefore must verify and adjust sp accordingly when taking an
exception from kernel mode since sp might not necessarily be 64-bit
aligned if the exception occurs in the middle of a kernel function.
If the exception occurs while in user mode then no sp fixup is needed as
long as sizeof(struct pt_regs) as well as any additional syscall data
stack space remain multiples of 8.
Signed-off-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Fix show_regs() to provide a backtrace. Provide a new __show_regs()
function which implements the common subset of show_regs() and die().
Add prototypes to asm-arm/system.h
Signed-off-by: Russell King <rmk@arm.linux.org.uk>
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Will Deacon