user/sven/linux.git/kernel/extable.c, branch v4.2.4

ftrace/x86/extable: Add is_ftrace_trampoline() function

2014-11-19T20:25:26Z

Stack traces that happen from function tracing check if the address on the stack is a __kernel_text_address(). That is, is the address kernel code. This calls core_kernel_text() which returns true if the address is part of the builtin kernel code. It also calls is_module_text_address() which returns true if the address belongs to module code. But what is missing is ftrace dynamically allocated trampolines. These trampolines are allocated for individual ftrace_ops that call the ftrace_ops callback functions directly. But if they do a stack trace, the code checking the stack wont detect them as they are neither core kernel code nor module address space. Adding another field to ftrace_ops that also stores the size of the trampoline assigned to it we can create a new function called is_ftrace_trampoline() that returns true if the address is a dynamically allocate ftrace trampoline. Note, it ignores trampolines that are not dynamically allocated as they will return true with the core_kernel_text() function. Link: http://lkml.kernel.org/r/20141119034829.497125839@goodmis.org Cc: Ingo Molnar Cc: "H. Peter Anvin" Acked-by: Thomas Gleixner Signed-off-by: Steven Rostedt

asmlinkage: Make main_extable_sort_needed visible

2014-02-14T02:13:22Z

main_extable_sort_needed is used by the build system and needs to be a normal ELF symbol. Make it visible so that LTO does not remove or mangle it. Signed-off-by: Andi Kleen Link: http://lkml.kernel.org/r/1391845930-28580-8-git-send-email-ak@linux.intel.com Signed-off-by: H. Peter Anvin

kernel/extable: fix address-checks for core_kernel and init areas

2013-11-28T17:49:41Z

The init_kernel_text() and core_kernel_text() functions should not include the labels _einittext and _etext when checking if an address is inside the .text or .init sections. Signed-off-by: Helge Deller Signed-off-by: Linus Torvalds

extable: skip sorting if the table is empty

2013-09-11T22:58:25Z

At least on ARM no-MMU the extable is empty and so there is nothing to sort. So add a check for the table to be empty which effectively only changes that the misleading pr_notice is suppressed. Signed-off-by: Uwe Kleine-König Cc: Ingo Molnar Cc: David Daney Cc: "H. Peter Anvin" Cc: Borislav Petkov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

extable: Flip the sorting message

2013-04-15T11:25:16Z

Now that we do sort the __extable at build time, we actually are interested only in the case where we still do need to sort it. Signed-off-by: Borislav Petkov Cc: David Daney Link: http://lkml.kernel.org/r/1366023109-12098-1-git-send-email-bp@alien8.de Signed-off-by: Ingo Molnar

extable: Skip sorting if sorted at build time.

2012-04-19T22:06:55Z

If the build program sortextable has already sorted the exception table, don't sort it again. Signed-off-by: David Daney Link: http://lkml.kernel.org/r/1334872799-14589-3-git-send-email-ddaney.cavm@gmail.com Signed-off-by: H. Peter Anvin

extable, core_kernel_data(): Make sure all archs define _sdata

2011-05-20T06:56:56Z

A new utility function (core_kernel_data()) is used to determine if a passed in address is part of core kernel data or not. It may or may not return true for RO data, but this utility must work for RW data. Thus both _sdata and _edata must be defined and continuous, without .init sections that may later be freed and replaced by volatile memory (memory that can be freed). This utility function is used to determine if data is safe from ever being freed. Thus it should return true for all RW global data that is not in a module or has been allocated, or false otherwise. Also change core_kernel_data() back to the more precise _sdata condition and document the function. Signed-off-by: Steven Rostedt Acked-by: Ralf Baechle Acked-by: Hirokazu Takata Cc: Richard Henderson Cc: Ivan Kokshaysky Cc: Matt Turner Cc: Geert Uytterhoeven Cc: Roman Zippel Cc: linux-m68k@lists.linux-m68k.org Cc: Kyle McMartin Cc: Helge Deller Cc: JamesE.J.Bottomley Link: http://lkml.kernel.org/r/1305855298.1465.19.camel@gandalf.stny.rr.com Signed-off-by: Ingo Molnar ---- arch/alpha/kernel/vmlinux.lds.S | 1 + arch/m32r/kernel/vmlinux.lds.S | 1 + arch/m68k/kernel/vmlinux-std.lds | 2 ++ arch/m68k/kernel/vmlinux-sun3.lds | 1 + arch/mips/kernel/vmlinux.lds.S | 1 + arch/parisc/kernel/vmlinux.lds.S | 3 +++ kernel/extable.c | 12 +++++++++++- 7 files changed, 20 insertions(+), 1 deletion(-)

core_kernel_data(): Fix architectures that do not define _sdata

2011-05-19T23:27:16Z

Some architectures such as Alpha do not define _sdata but _data: kernel/built-in.o: In function `core_kernel_data': kernel/extable.c:77: undefined reference to `_sdata' So expand the scope of the data range to the text addresses too, this might be more correct anyway because this way we can cover readonly variables as well. Cc: Paul E. McKenney Cc: Steven Rostedt Link: http://lkml.kernel.org/n/tip-i878c8a0e0g0ep4v7i6vxnhz@git.kernel.org Signed-off-by: Ingo Molnar

ftrace: Allow dynamically allocated function tracers

2011-05-18T19:29:51Z

Now that functions may be selected individually, it only makes sense that we should allow dynamically allocated trace structures to be traced. This will allow perf to allocate a ftrace_ops structure at runtime and use it to pick and choose which functions that structure will trace. Note, a dynamically allocated ftrace_ops will always be called indirectly instead of being called directly from the mcount in entry.S. This is because there's no safe way to prevent mcount from being preempted before calling the function, unless we modify every entry.S to do so (not likely). Thus, dynamically allocated functions will now be called by the ftrace_ops_list_func() that loops through the ops that are allocated if there are more than one op allocated at a time. This loop is protected with a preempt_disable. To determine if an ftrace_ops structure is allocated or not, a new util function was added to the kernel/extable.c called core_kernel_data(), which returns 1 if the address is between _sdata and _edata. Cc: Paul E. McKenney Signed-off-by: Steven Rostedt

Merge branch 'tracing-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

2009-04-05T18:04:19Z

* 'tracing-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (413 commits) tracing, net: fix net tree and tracing tree merge interaction tracing, powerpc: fix powerpc tree and tracing tree interaction ring-buffer: do not remove reader page from list on ring buffer free function-graph: allow unregistering twice trace: make argument 'mem' of trace_seq_putmem() const tracing: add missing 'extern' keywords to trace_output.h tracing: provide trace_seq_reserve() blktrace: print out BLK_TN_MESSAGE properly blktrace: extract duplidate code blktrace: fix memory leak when freeing struct blk_io_trace blktrace: fix blk_probes_ref chaos blktrace: make classic output more classic blktrace: fix off-by-one bug blktrace: fix the original blktrace blktrace: fix a race when creating blk_tree_root in debugfs blktrace: fix timestamp in binary output tracing, Text Edit Lock: cleanup tracing: filter fix for TRACE_EVENT_FORMAT events ftrace: Using FTRACE_WARN_ON() to check "freed record" in ftrace_release() x86: kretprobe-booster interrupt emulation code fix ... Fix up trivial conflicts in arch/parisc/include/asm/ftrace.h include/linux/memory.h kernel/extable.c kernel/module.c