2017-11-24 22:00:32 +08:00
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// SPDX-License-Identifier: GPL-2.0+
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2006-09-20 21:58:39 +08:00
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/*
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* Kernel Probes (KProbes)
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*
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2012-07-20 17:15:04 +08:00
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* Copyright IBM Corp. 2002, 2006
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2006-09-20 21:58:39 +08:00
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*
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* s390 port, used ppc64 as template. Mike Grundy <grundym@us.ibm.com>
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*/
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#include <linux/kprobes.h>
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#include <linux/ptrace.h>
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#include <linux/preempt.h>
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#include <linux/stop_machine.h>
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2007-05-08 15:27:03 +08:00
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#include <linux/kdebug.h>
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2009-06-12 16:26:43 +08:00
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#include <linux/uaccess.h>
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2016-09-20 05:54:56 +08:00
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#include <linux/extable.h>
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2006-09-20 21:58:39 +08:00
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#include <linux/module.h>
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include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.
percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.
http://userweb.kernel.org/~tj/misc/slabh-sweep.py
The script does the followings.
* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.
* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.
* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.
The conversion was done in the following steps.
1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.
2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.
3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.
4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.
5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.
6. percpu.h was updated not to include slab.h.
7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).
* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig
8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.
Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.
Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-24 16:04:11 +08:00
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#include <linux/slab.h>
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2010-11-10 17:05:57 +08:00
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#include <linux/hardirq.h>
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2014-10-15 18:17:38 +08:00
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#include <linux/ftrace.h>
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2017-05-09 06:58:08 +08:00
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#include <asm/set_memory.h>
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2013-09-13 19:59:26 +08:00
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#include <asm/sections.h>
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#include <asm/dis.h>
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2006-09-20 21:58:39 +08:00
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2011-01-05 19:47:24 +08:00
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DEFINE_PER_CPU(struct kprobe *, current_kprobe);
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2006-09-20 21:58:39 +08:00
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DEFINE_PER_CPU(struct kprobe_ctlblk, kprobe_ctlblk);
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2011-01-05 19:47:24 +08:00
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struct kretprobe_blackpoint kretprobe_blacklist[] = { };
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2007-10-16 16:27:49 +08:00
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2019-02-04 04:36:46 +08:00
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DEFINE_INSN_CACHE_OPS(s390_insn);
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2013-09-12 05:24:14 +08:00
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2019-02-04 04:36:46 +08:00
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static int insn_page_in_use;
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static char insn_page[PAGE_SIZE] __aligned(PAGE_SIZE);
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2016-03-22 17:54:24 +08:00
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2019-02-04 04:36:46 +08:00
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static void *alloc_s390_insn_page(void)
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{
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if (xchg(&insn_page_in_use, 1) == 1)
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return NULL;
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set_memory_x((unsigned long) &insn_page, 1);
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return &insn_page;
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2013-09-12 05:24:14 +08:00
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}
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2019-02-04 04:36:46 +08:00
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static void free_s390_insn_page(void *page)
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2013-09-12 05:24:14 +08:00
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{
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2016-03-22 17:54:24 +08:00
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set_memory_nx((unsigned long) page, 1);
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2019-02-04 04:36:46 +08:00
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xchg(&insn_page_in_use, 0);
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2013-09-12 05:24:14 +08:00
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}
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2019-02-04 04:36:46 +08:00
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struct kprobe_insn_cache kprobe_s390_insn_slots = {
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.mutex = __MUTEX_INITIALIZER(kprobe_s390_insn_slots.mutex),
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.alloc = alloc_s390_insn_page,
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.free = free_s390_insn_page,
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.pages = LIST_HEAD_INIT(kprobe_s390_insn_slots.pages),
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2013-09-12 05:24:14 +08:00
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.insn_size = MAX_INSN_SIZE,
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};
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2014-10-22 18:42:38 +08:00
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static void copy_instruction(struct kprobe *p)
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2013-09-12 05:24:14 +08:00
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{
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s64 disp, new_disp;
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u64 addr, new_addr;
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2020-01-21 19:31:47 +08:00
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memcpy(p->ainsn.insn, p->addr, insn_length(*p->addr >> 8));
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2014-10-15 18:17:38 +08:00
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p->opcode = p->ainsn.insn[0];
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2014-09-22 22:37:27 +08:00
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if (!probe_is_insn_relative_long(p->ainsn.insn))
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2013-09-12 05:24:14 +08:00
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return;
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/*
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* For pc-relative instructions in RIL-b or RIL-c format patch the
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* RI2 displacement field. We have already made sure that the insn
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* slot for the patched instruction is within the same 2GB area
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* as the original instruction (either kernel image or module area).
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* Therefore the new displacement will always fit.
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*/
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disp = *(s32 *)&p->ainsn.insn[1];
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addr = (u64)(unsigned long)p->addr;
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new_addr = (u64)(unsigned long)p->ainsn.insn;
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new_disp = ((addr + (disp * 2)) - new_addr) / 2;
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*(s32 *)&p->ainsn.insn[1] = new_disp;
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}
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2014-10-22 18:42:38 +08:00
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NOKPROBE_SYMBOL(copy_instruction);
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2013-09-12 05:24:14 +08:00
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static inline int is_kernel_addr(void *addr)
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{
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return addr < (void *)_end;
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}
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2014-10-22 18:42:38 +08:00
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static int s390_get_insn_slot(struct kprobe *p)
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2013-09-12 05:24:14 +08:00
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{
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/*
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* Get an insn slot that is within the same 2GB area like the original
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* instruction. That way instructions with a 32bit signed displacement
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* field can be patched and executed within the insn slot.
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*/
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p->ainsn.insn = NULL;
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if (is_kernel_addr(p->addr))
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2019-02-04 04:36:46 +08:00
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p->ainsn.insn = get_s390_insn_slot();
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2013-09-02 16:31:11 +08:00
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else if (is_module_addr(p->addr))
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2013-09-12 05:24:14 +08:00
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p->ainsn.insn = get_insn_slot();
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return p->ainsn.insn ? 0 : -ENOMEM;
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}
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2014-10-22 18:42:38 +08:00
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NOKPROBE_SYMBOL(s390_get_insn_slot);
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2013-09-12 05:24:14 +08:00
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2014-10-22 18:42:38 +08:00
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static void s390_free_insn_slot(struct kprobe *p)
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2013-09-12 05:24:14 +08:00
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{
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if (!p->ainsn.insn)
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return;
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if (is_kernel_addr(p->addr))
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2019-02-04 04:36:46 +08:00
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free_s390_insn_slot(p->ainsn.insn, 0);
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2013-09-12 05:24:14 +08:00
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else
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free_insn_slot(p->ainsn.insn, 0);
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p->ainsn.insn = NULL;
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}
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2014-10-22 18:42:38 +08:00
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NOKPROBE_SYMBOL(s390_free_insn_slot);
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2013-09-12 05:24:14 +08:00
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2014-10-22 18:42:38 +08:00
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int arch_prepare_kprobe(struct kprobe *p)
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2011-01-05 19:47:19 +08:00
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{
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if ((unsigned long) p->addr & 0x01)
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return -EINVAL;
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/* Make sure the probe isn't going on a difficult instruction */
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2014-09-22 22:37:27 +08:00
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if (probe_is_prohibited_opcode(p->addr))
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2011-01-05 19:47:19 +08:00
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return -EINVAL;
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2013-09-12 05:24:14 +08:00
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if (s390_get_insn_slot(p))
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return -ENOMEM;
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copy_instruction(p);
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2011-01-05 19:47:19 +08:00
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return 0;
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2006-09-20 21:58:39 +08:00
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}
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2014-10-22 18:42:38 +08:00
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NOKPROBE_SYMBOL(arch_prepare_kprobe);
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2006-09-20 21:58:39 +08:00
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2014-10-15 18:17:38 +08:00
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struct swap_insn_args {
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struct kprobe *p;
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unsigned int arm_kprobe : 1;
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2011-01-05 19:47:18 +08:00
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};
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2014-10-22 18:42:38 +08:00
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static int swap_instruction(void *data)
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2006-09-20 21:58:39 +08:00
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{
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2014-10-15 18:17:38 +08:00
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struct swap_insn_args *args = data;
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struct kprobe *p = args->p;
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2020-01-21 19:31:47 +08:00
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u16 opc;
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opc = args->arm_kprobe ? BREAKPOINT_INSTRUCTION : p->opcode;
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s390_kernel_write(p->addr, &opc, sizeof(opc));
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2011-01-05 19:47:18 +08:00
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return 0;
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2006-09-20 21:58:39 +08:00
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}
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2014-10-22 18:42:38 +08:00
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NOKPROBE_SYMBOL(swap_instruction);
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2006-09-20 21:58:39 +08:00
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2014-10-22 18:42:38 +08:00
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void arch_arm_kprobe(struct kprobe *p)
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2006-09-20 21:58:39 +08:00
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{
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2014-10-15 18:17:38 +08:00
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struct swap_insn_args args = {.p = p, .arm_kprobe = 1};
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2006-09-20 21:58:39 +08:00
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2017-05-24 16:15:39 +08:00
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stop_machine_cpuslocked(swap_instruction, &args, NULL);
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2006-09-20 21:58:39 +08:00
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}
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2014-10-22 18:42:38 +08:00
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NOKPROBE_SYMBOL(arch_arm_kprobe);
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2006-09-20 21:58:39 +08:00
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2014-10-22 18:42:38 +08:00
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void arch_disarm_kprobe(struct kprobe *p)
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2006-09-20 21:58:39 +08:00
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{
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2014-10-15 18:17:38 +08:00
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struct swap_insn_args args = {.p = p, .arm_kprobe = 0};
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2006-09-20 21:58:39 +08:00
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2017-05-24 16:15:39 +08:00
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stop_machine_cpuslocked(swap_instruction, &args, NULL);
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2006-09-20 21:58:39 +08:00
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}
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2014-10-22 18:42:38 +08:00
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NOKPROBE_SYMBOL(arch_disarm_kprobe);
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2006-09-20 21:58:39 +08:00
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2014-10-22 18:42:38 +08:00
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void arch_remove_kprobe(struct kprobe *p)
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2006-09-20 21:58:39 +08:00
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{
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2013-09-12 05:24:14 +08:00
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s390_free_insn_slot(p);
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2006-09-20 21:58:39 +08:00
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}
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2014-10-22 18:42:38 +08:00
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NOKPROBE_SYMBOL(arch_remove_kprobe);
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2006-09-20 21:58:39 +08:00
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2014-10-22 18:42:38 +08:00
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static void enable_singlestep(struct kprobe_ctlblk *kcb,
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struct pt_regs *regs,
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unsigned long ip)
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2006-09-20 21:58:39 +08:00
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{
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2011-01-05 19:48:10 +08:00
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struct per_regs per_kprobe;
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2006-09-20 21:58:39 +08:00
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2011-01-05 19:48:10 +08:00
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/* Set up the PER control registers %cr9-%cr11 */
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per_kprobe.control = PER_EVENT_IFETCH;
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per_kprobe.start = ip;
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per_kprobe.end = ip;
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2006-09-20 21:58:39 +08:00
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2011-01-05 19:47:17 +08:00
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/* Save control regs and psw mask */
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__ctl_store(kcb->kprobe_saved_ctl, 9, 11);
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kcb->kprobe_saved_imask = regs->psw.mask &
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(PSW_MASK_PER | PSW_MASK_IO | PSW_MASK_EXT);
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/* Set PER control regs, turns on single step for the given address */
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2011-01-05 19:48:10 +08:00
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__ctl_load(per_kprobe, 9, 11);
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2006-09-20 21:58:39 +08:00
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regs->psw.mask |= PSW_MASK_PER;
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2010-11-10 17:05:57 +08:00
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regs->psw.mask &= ~(PSW_MASK_IO | PSW_MASK_EXT);
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2016-01-18 19:49:44 +08:00
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regs->psw.addr = ip;
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2006-09-20 21:58:39 +08:00
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}
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2014-10-22 18:42:38 +08:00
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NOKPROBE_SYMBOL(enable_singlestep);
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2006-09-20 21:58:39 +08:00
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2014-10-22 18:42:38 +08:00
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static void disable_singlestep(struct kprobe_ctlblk *kcb,
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struct pt_regs *regs,
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unsigned long ip)
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2011-01-05 19:47:17 +08:00
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{
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/* Restore control regs and psw mask, set new psw address */
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__ctl_load(kcb->kprobe_saved_ctl, 9, 11);
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regs->psw.mask &= ~PSW_MASK_PER;
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regs->psw.mask |= kcb->kprobe_saved_imask;
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2016-01-18 19:49:44 +08:00
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regs->psw.addr = ip;
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2011-01-05 19:47:17 +08:00
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}
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2014-10-22 18:42:38 +08:00
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NOKPROBE_SYMBOL(disable_singlestep);
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2011-01-05 19:47:17 +08:00
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2011-01-05 19:47:20 +08:00
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/*
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* Activate a kprobe by storing its pointer to current_kprobe. The
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* previous kprobe is stored in kcb->prev_kprobe. A stack of up to
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* two kprobes can be active, see KPROBE_REENTER.
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*/
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2014-10-22 18:42:38 +08:00
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static void push_kprobe(struct kprobe_ctlblk *kcb, struct kprobe *p)
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2006-09-20 21:58:39 +08:00
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{
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s390: Replace __get_cpu_var uses
__get_cpu_var() is used for multiple purposes in the kernel source. One of
them is address calculation via the form &__get_cpu_var(x). This calculates
the address for the instance of the percpu variable of the current processor
based on an offset.
Other use cases are for storing and retrieving data from the current
processors percpu area. __get_cpu_var() can be used as an lvalue when
writing data or on the right side of an assignment.
__get_cpu_var() is defined as :
#define __get_cpu_var(var) (*this_cpu_ptr(&(var)))
__get_cpu_var() always only does an address determination. However, store
and retrieve operations could use a segment prefix (or global register on
other platforms) to avoid the address calculation.
this_cpu_write() and this_cpu_read() can directly take an offset into a
percpu area and use optimized assembly code to read and write per cpu
variables.
This patch converts __get_cpu_var into either an explicit address
calculation using this_cpu_ptr() or into a use of this_cpu operations that
use the offset. Thereby address calculations are avoided and less registers
are used when code is generated.
At the end of the patch set all uses of __get_cpu_var have been removed so
the macro is removed too.
The patch set includes passes over all arches as well. Once these operations
are used throughout then specialized macros can be defined in non -x86
arches as well in order to optimize per cpu access by f.e. using a global
register that may be set to the per cpu base.
Transformations done to __get_cpu_var()
1. Determine the address of the percpu instance of the current processor.
DEFINE_PER_CPU(int, y);
int *x = &__get_cpu_var(y);
Converts to
int *x = this_cpu_ptr(&y);
2. Same as #1 but this time an array structure is involved.
DEFINE_PER_CPU(int, y[20]);
int *x = __get_cpu_var(y);
Converts to
int *x = this_cpu_ptr(y);
3. Retrieve the content of the current processors instance of a per cpu
variable.
DEFINE_PER_CPU(int, y);
int x = __get_cpu_var(y)
Converts to
int x = __this_cpu_read(y);
4. Retrieve the content of a percpu struct
DEFINE_PER_CPU(struct mystruct, y);
struct mystruct x = __get_cpu_var(y);
Converts to
memcpy(&x, this_cpu_ptr(&y), sizeof(x));
5. Assignment to a per cpu variable
DEFINE_PER_CPU(int, y)
__get_cpu_var(y) = x;
Converts to
this_cpu_write(y, x);
6. Increment/Decrement etc of a per cpu variable
DEFINE_PER_CPU(int, y);
__get_cpu_var(y)++
Converts to
this_cpu_inc(y)
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
CC: linux390@de.ibm.com
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2014-08-18 01:30:45 +08:00
|
|
|
kcb->prev_kprobe.kp = __this_cpu_read(current_kprobe);
|
2006-09-20 21:58:39 +08:00
|
|
|
kcb->prev_kprobe.status = kcb->kprobe_status;
|
s390: Replace __get_cpu_var uses
__get_cpu_var() is used for multiple purposes in the kernel source. One of
them is address calculation via the form &__get_cpu_var(x). This calculates
the address for the instance of the percpu variable of the current processor
based on an offset.
Other use cases are for storing and retrieving data from the current
processors percpu area. __get_cpu_var() can be used as an lvalue when
writing data or on the right side of an assignment.
__get_cpu_var() is defined as :
#define __get_cpu_var(var) (*this_cpu_ptr(&(var)))
__get_cpu_var() always only does an address determination. However, store
and retrieve operations could use a segment prefix (or global register on
other platforms) to avoid the address calculation.
this_cpu_write() and this_cpu_read() can directly take an offset into a
percpu area and use optimized assembly code to read and write per cpu
variables.
This patch converts __get_cpu_var into either an explicit address
calculation using this_cpu_ptr() or into a use of this_cpu operations that
use the offset. Thereby address calculations are avoided and less registers
are used when code is generated.
At the end of the patch set all uses of __get_cpu_var have been removed so
the macro is removed too.
The patch set includes passes over all arches as well. Once these operations
are used throughout then specialized macros can be defined in non -x86
arches as well in order to optimize per cpu access by f.e. using a global
register that may be set to the per cpu base.
Transformations done to __get_cpu_var()
1. Determine the address of the percpu instance of the current processor.
DEFINE_PER_CPU(int, y);
int *x = &__get_cpu_var(y);
Converts to
int *x = this_cpu_ptr(&y);
2. Same as #1 but this time an array structure is involved.
DEFINE_PER_CPU(int, y[20]);
int *x = __get_cpu_var(y);
Converts to
int *x = this_cpu_ptr(y);
3. Retrieve the content of the current processors instance of a per cpu
variable.
DEFINE_PER_CPU(int, y);
int x = __get_cpu_var(y)
Converts to
int x = __this_cpu_read(y);
4. Retrieve the content of a percpu struct
DEFINE_PER_CPU(struct mystruct, y);
struct mystruct x = __get_cpu_var(y);
Converts to
memcpy(&x, this_cpu_ptr(&y), sizeof(x));
5. Assignment to a per cpu variable
DEFINE_PER_CPU(int, y)
__get_cpu_var(y) = x;
Converts to
this_cpu_write(y, x);
6. Increment/Decrement etc of a per cpu variable
DEFINE_PER_CPU(int, y);
__get_cpu_var(y)++
Converts to
this_cpu_inc(y)
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
CC: linux390@de.ibm.com
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2014-08-18 01:30:45 +08:00
|
|
|
__this_cpu_write(current_kprobe, p);
|
2006-09-20 21:58:39 +08:00
|
|
|
}
|
2014-10-22 18:42:38 +08:00
|
|
|
NOKPROBE_SYMBOL(push_kprobe);
|
2006-09-20 21:58:39 +08:00
|
|
|
|
2011-01-05 19:47:20 +08:00
|
|
|
/*
|
|
|
|
|
* Deactivate a kprobe by backing up to the previous state. If the
|
|
|
|
|
* current state is KPROBE_REENTER prev_kprobe.kp will be non-NULL,
|
|
|
|
|
* for any other state prev_kprobe.kp will be NULL.
|
|
|
|
|
*/
|
2014-10-22 18:42:38 +08:00
|
|
|
static void pop_kprobe(struct kprobe_ctlblk *kcb)
|
2006-09-20 21:58:39 +08:00
|
|
|
{
|
s390: Replace __get_cpu_var uses
__get_cpu_var() is used for multiple purposes in the kernel source. One of
them is address calculation via the form &__get_cpu_var(x). This calculates
the address for the instance of the percpu variable of the current processor
based on an offset.
Other use cases are for storing and retrieving data from the current
processors percpu area. __get_cpu_var() can be used as an lvalue when
writing data or on the right side of an assignment.
__get_cpu_var() is defined as :
#define __get_cpu_var(var) (*this_cpu_ptr(&(var)))
__get_cpu_var() always only does an address determination. However, store
and retrieve operations could use a segment prefix (or global register on
other platforms) to avoid the address calculation.
this_cpu_write() and this_cpu_read() can directly take an offset into a
percpu area and use optimized assembly code to read and write per cpu
variables.
This patch converts __get_cpu_var into either an explicit address
calculation using this_cpu_ptr() or into a use of this_cpu operations that
use the offset. Thereby address calculations are avoided and less registers
are used when code is generated.
At the end of the patch set all uses of __get_cpu_var have been removed so
the macro is removed too.
The patch set includes passes over all arches as well. Once these operations
are used throughout then specialized macros can be defined in non -x86
arches as well in order to optimize per cpu access by f.e. using a global
register that may be set to the per cpu base.
Transformations done to __get_cpu_var()
1. Determine the address of the percpu instance of the current processor.
DEFINE_PER_CPU(int, y);
int *x = &__get_cpu_var(y);
Converts to
int *x = this_cpu_ptr(&y);
2. Same as #1 but this time an array structure is involved.
DEFINE_PER_CPU(int, y[20]);
int *x = __get_cpu_var(y);
Converts to
int *x = this_cpu_ptr(y);
3. Retrieve the content of the current processors instance of a per cpu
variable.
DEFINE_PER_CPU(int, y);
int x = __get_cpu_var(y)
Converts to
int x = __this_cpu_read(y);
4. Retrieve the content of a percpu struct
DEFINE_PER_CPU(struct mystruct, y);
struct mystruct x = __get_cpu_var(y);
Converts to
memcpy(&x, this_cpu_ptr(&y), sizeof(x));
5. Assignment to a per cpu variable
DEFINE_PER_CPU(int, y)
__get_cpu_var(y) = x;
Converts to
this_cpu_write(y, x);
6. Increment/Decrement etc of a per cpu variable
DEFINE_PER_CPU(int, y);
__get_cpu_var(y)++
Converts to
this_cpu_inc(y)
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
CC: linux390@de.ibm.com
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2014-08-18 01:30:45 +08:00
|
|
|
__this_cpu_write(current_kprobe, kcb->prev_kprobe.kp);
|
2006-09-20 21:58:39 +08:00
|
|
|
kcb->kprobe_status = kcb->prev_kprobe.status;
|
|
|
|
|
}
|
2014-10-22 18:42:38 +08:00
|
|
|
NOKPROBE_SYMBOL(pop_kprobe);
|
2006-09-20 21:58:39 +08:00
|
|
|
|
2014-10-22 18:42:38 +08:00
|
|
|
void arch_prepare_kretprobe(struct kretprobe_instance *ri, struct pt_regs *regs)
|
2006-09-20 21:58:39 +08:00
|
|
|
{
|
2007-05-08 15:34:14 +08:00
|
|
|
ri->ret_addr = (kprobe_opcode_t *) regs->gprs[14];
|
2006-09-20 21:58:39 +08:00
|
|
|
|
2007-05-08 15:34:14 +08:00
|
|
|
/* Replace the return addr with trampoline addr */
|
2011-01-05 19:47:24 +08:00
|
|
|
regs->gprs[14] = (unsigned long) &kretprobe_trampoline;
|
2006-09-20 21:58:39 +08:00
|
|
|
}
|
2014-10-22 18:42:38 +08:00
|
|
|
NOKPROBE_SYMBOL(arch_prepare_kretprobe);
|
2006-09-20 21:58:39 +08:00
|
|
|
|
2014-10-22 18:42:38 +08:00
|
|
|
static void kprobe_reenter_check(struct kprobe_ctlblk *kcb, struct kprobe *p)
|
2011-01-05 19:47:23 +08:00
|
|
|
{
|
|
|
|
|
switch (kcb->kprobe_status) {
|
|
|
|
|
case KPROBE_HIT_SSDONE:
|
|
|
|
|
case KPROBE_HIT_ACTIVE:
|
|
|
|
|
kprobes_inc_nmissed_count(p);
|
|
|
|
|
break;
|
|
|
|
|
case KPROBE_HIT_SS:
|
|
|
|
|
case KPROBE_REENTER:
|
|
|
|
|
default:
|
|
|
|
|
/*
|
|
|
|
|
* A kprobe on the code path to single step an instruction
|
|
|
|
|
* is a BUG. The code path resides in the .kprobes.text
|
|
|
|
|
* section and is executed with interrupts disabled.
|
|
|
|
|
*/
|
2018-01-25 13:30:32 +08:00
|
|
|
pr_err("Invalid kprobe detected.\n");
|
2011-01-05 19:47:23 +08:00
|
|
|
dump_kprobe(p);
|
|
|
|
|
BUG();
|
|
|
|
|
}
|
|
|
|
|
}
|
2014-10-22 18:42:38 +08:00
|
|
|
NOKPROBE_SYMBOL(kprobe_reenter_check);
|
2011-01-05 19:47:23 +08:00
|
|
|
|
2014-10-22 18:42:38 +08:00
|
|
|
static int kprobe_handler(struct pt_regs *regs)
|
2006-09-20 21:58:39 +08:00
|
|
|
{
|
|
|
|
|
struct kprobe_ctlblk *kcb;
|
2011-01-05 19:47:23 +08:00
|
|
|
struct kprobe *p;
|
2006-09-20 21:58:39 +08:00
|
|
|
|
|
|
|
|
/*
|
2011-01-05 19:47:23 +08:00
|
|
|
* We want to disable preemption for the entire duration of kprobe
|
|
|
|
|
* processing. That includes the calls to the pre/post handlers
|
|
|
|
|
* and single stepping the kprobe instruction.
|
2006-09-20 21:58:39 +08:00
|
|
|
*/
|
|
|
|
|
preempt_disable();
|
|
|
|
|
kcb = get_kprobe_ctlblk();
|
2016-01-18 20:12:19 +08:00
|
|
|
p = get_kprobe((void *)(regs->psw.addr - 2));
|
2006-09-20 21:58:39 +08:00
|
|
|
|
2011-01-05 19:47:23 +08:00
|
|
|
if (p) {
|
|
|
|
|
if (kprobe_running()) {
|
2011-01-05 19:47:20 +08:00
|
|
|
/*
|
|
|
|
|
* We have hit a kprobe while another is still
|
|
|
|
|
* active. This can happen in the pre and post
|
|
|
|
|
* handler. Single step the instruction of the
|
|
|
|
|
* new probe but do not call any handler function
|
|
|
|
|
* of this secondary kprobe.
|
|
|
|
|
* push_kprobe and pop_kprobe saves and restores
|
|
|
|
|
* the currently active kprobe.
|
2006-09-20 21:58:39 +08:00
|
|
|
*/
|
2011-01-05 19:47:23 +08:00
|
|
|
kprobe_reenter_check(kcb, p);
|
2011-01-05 19:47:20 +08:00
|
|
|
push_kprobe(kcb, p);
|
2006-09-20 21:58:39 +08:00
|
|
|
kcb->kprobe_status = KPROBE_REENTER;
|
|
|
|
|
} else {
|
2011-01-05 19:47:23 +08:00
|
|
|
/*
|
|
|
|
|
* If we have no pre-handler or it returned 0, we
|
|
|
|
|
* continue with single stepping. If we have a
|
|
|
|
|
* pre-handler and it returned non-zero, it prepped
|
2018-06-20 00:08:59 +08:00
|
|
|
* for changing execution path, so get out doing
|
|
|
|
|
* nothing more here.
|
2011-01-05 19:47:23 +08:00
|
|
|
*/
|
|
|
|
|
push_kprobe(kcb, p);
|
|
|
|
|
kcb->kprobe_status = KPROBE_HIT_ACTIVE;
|
2018-06-20 00:15:45 +08:00
|
|
|
if (p->pre_handler && p->pre_handler(p, regs)) {
|
|
|
|
|
pop_kprobe(kcb);
|
|
|
|
|
preempt_enable_no_resched();
|
2011-01-05 19:47:23 +08:00
|
|
|
return 1;
|
2018-06-20 00:15:45 +08:00
|
|
|
}
|
2011-01-05 19:47:23 +08:00
|
|
|
kcb->kprobe_status = KPROBE_HIT_SS;
|
2006-09-20 21:58:39 +08:00
|
|
|
}
|
2011-01-05 19:47:23 +08:00
|
|
|
enable_singlestep(kcb, regs, (unsigned long) p->ainsn.insn);
|
2006-09-20 21:58:39 +08:00
|
|
|
return 1;
|
2011-01-05 19:47:23 +08:00
|
|
|
} /* else:
|
|
|
|
|
* No kprobe at this address and no active kprobe. The trap has
|
|
|
|
|
* not been caused by a kprobe breakpoint. The race of breakpoint
|
|
|
|
|
* vs. kprobe remove does not exist because on s390 as we use
|
|
|
|
|
* stop_machine to arm/disarm the breakpoints.
|
|
|
|
|
*/
|
2006-09-20 21:58:39 +08:00
|
|
|
preempt_enable_no_resched();
|
2011-01-05 19:47:23 +08:00
|
|
|
return 0;
|
2006-09-20 21:58:39 +08:00
|
|
|
}
|
2014-10-22 18:42:38 +08:00
|
|
|
NOKPROBE_SYMBOL(kprobe_handler);
|
2006-09-20 21:58:39 +08:00
|
|
|
|
|
|
|
|
/*
|
|
|
|
|
* Function return probe trampoline:
|
|
|
|
|
* - init_kprobes() establishes a probepoint here
|
|
|
|
|
* - When the probed function returns, this probe
|
|
|
|
|
* causes the handlers to fire
|
|
|
|
|
*/
|
2008-04-17 13:46:26 +08:00
|
|
|
static void __used kretprobe_trampoline_holder(void)
|
2006-09-20 21:58:39 +08:00
|
|
|
{
|
|
|
|
|
asm volatile(".global kretprobe_trampoline\n"
|
|
|
|
|
"kretprobe_trampoline: bcr 0,0\n");
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
/*
|
|
|
|
|
* Called when the probe at kretprobe trampoline is hit
|
|
|
|
|
*/
|
2014-10-22 18:42:38 +08:00
|
|
|
static int trampoline_probe_handler(struct kprobe *p, struct pt_regs *regs)
|
2006-09-20 21:58:39 +08:00
|
|
|
{
|
2011-01-05 19:47:24 +08:00
|
|
|
struct kretprobe_instance *ri;
|
2006-10-02 17:17:35 +08:00
|
|
|
struct hlist_head *head, empty_rp;
|
hlist: drop the node parameter from iterators
I'm not sure why, but the hlist for each entry iterators were conceived
list_for_each_entry(pos, head, member)
The hlist ones were greedy and wanted an extra parameter:
hlist_for_each_entry(tpos, pos, head, member)
Why did they need an extra pos parameter? I'm not quite sure. Not only
they don't really need it, it also prevents the iterator from looking
exactly like the list iterator, which is unfortunate.
Besides the semantic patch, there was some manual work required:
- Fix up the actual hlist iterators in linux/list.h
- Fix up the declaration of other iterators based on the hlist ones.
- A very small amount of places were using the 'node' parameter, this
was modified to use 'obj->member' instead.
- Coccinelle didn't handle the hlist_for_each_entry_safe iterator
properly, so those had to be fixed up manually.
The semantic patch which is mostly the work of Peter Senna Tschudin is here:
@@
iterator name hlist_for_each_entry, hlist_for_each_entry_continue, hlist_for_each_entry_from, hlist_for_each_entry_rcu, hlist_for_each_entry_rcu_bh, hlist_for_each_entry_continue_rcu_bh, for_each_busy_worker, ax25_uid_for_each, ax25_for_each, inet_bind_bucket_for_each, sctp_for_each_hentry, sk_for_each, sk_for_each_rcu, sk_for_each_from, sk_for_each_safe, sk_for_each_bound, hlist_for_each_entry_safe, hlist_for_each_entry_continue_rcu, nr_neigh_for_each, nr_neigh_for_each_safe, nr_node_for_each, nr_node_for_each_safe, for_each_gfn_indirect_valid_sp, for_each_gfn_sp, for_each_host;
type T;
expression a,c,d,e;
identifier b;
statement S;
@@
-T b;
<+... when != b
(
hlist_for_each_entry(a,
- b,
c, d) S
|
hlist_for_each_entry_continue(a,
- b,
c) S
|
hlist_for_each_entry_from(a,
- b,
c) S
|
hlist_for_each_entry_rcu(a,
- b,
c, d) S
|
hlist_for_each_entry_rcu_bh(a,
- b,
c, d) S
|
hlist_for_each_entry_continue_rcu_bh(a,
- b,
c) S
|
for_each_busy_worker(a, c,
- b,
d) S
|
ax25_uid_for_each(a,
- b,
c) S
|
ax25_for_each(a,
- b,
c) S
|
inet_bind_bucket_for_each(a,
- b,
c) S
|
sctp_for_each_hentry(a,
- b,
c) S
|
sk_for_each(a,
- b,
c) S
|
sk_for_each_rcu(a,
- b,
c) S
|
sk_for_each_from
-(a, b)
+(a)
S
+ sk_for_each_from(a) S
|
sk_for_each_safe(a,
- b,
c, d) S
|
sk_for_each_bound(a,
- b,
c) S
|
hlist_for_each_entry_safe(a,
- b,
c, d, e) S
|
hlist_for_each_entry_continue_rcu(a,
- b,
c) S
|
nr_neigh_for_each(a,
- b,
c) S
|
nr_neigh_for_each_safe(a,
- b,
c, d) S
|
nr_node_for_each(a,
- b,
c) S
|
nr_node_for_each_safe(a,
- b,
c, d) S
|
- for_each_gfn_sp(a, c, d, b) S
+ for_each_gfn_sp(a, c, d) S
|
- for_each_gfn_indirect_valid_sp(a, c, d, b) S
+ for_each_gfn_indirect_valid_sp(a, c, d) S
|
for_each_host(a,
- b,
c) S
|
for_each_host_safe(a,
- b,
c, d) S
|
for_each_mesh_entry(a,
- b,
c, d) S
)
...+>
[akpm@linux-foundation.org: drop bogus change from net/ipv4/raw.c]
[akpm@linux-foundation.org: drop bogus hunk from net/ipv6/raw.c]
[akpm@linux-foundation.org: checkpatch fixes]
[akpm@linux-foundation.org: fix warnings]
[akpm@linux-foudnation.org: redo intrusive kvm changes]
Tested-by: Peter Senna Tschudin <peter.senna@gmail.com>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-28 09:06:00 +08:00
|
|
|
struct hlist_node *tmp;
|
2011-01-05 19:47:24 +08:00
|
|
|
unsigned long flags, orig_ret_address;
|
|
|
|
|
unsigned long trampoline_address;
|
|
|
|
|
kprobe_opcode_t *correct_ret_addr;
|
2006-09-20 21:58:39 +08:00
|
|
|
|
2006-10-02 17:17:35 +08:00
|
|
|
INIT_HLIST_HEAD(&empty_rp);
|
2008-07-25 16:46:04 +08:00
|
|
|
kretprobe_hash_lock(current, &head, &flags);
|
2006-09-20 21:58:39 +08:00
|
|
|
|
|
|
|
|
/*
|
|
|
|
|
* It is possible to have multiple instances associated with a given
|
|
|
|
|
* task either because an multiple functions in the call path
|
2008-10-17 01:02:37 +08:00
|
|
|
* have a return probe installed on them, and/or more than one return
|
2006-09-20 21:58:39 +08:00
|
|
|
* return probe was registered for a target function.
|
|
|
|
|
*
|
|
|
|
|
* We can handle this because:
|
|
|
|
|
* - instances are always inserted at the head of the list
|
|
|
|
|
* - when multiple return probes are registered for the same
|
|
|
|
|
* function, the first instance's ret_addr will point to the
|
|
|
|
|
* real return address, and all the rest will point to
|
|
|
|
|
* kretprobe_trampoline
|
|
|
|
|
*/
|
2011-01-05 19:47:24 +08:00
|
|
|
ri = NULL;
|
|
|
|
|
orig_ret_address = 0;
|
|
|
|
|
correct_ret_addr = NULL;
|
|
|
|
|
trampoline_address = (unsigned long) &kretprobe_trampoline;
|
hlist: drop the node parameter from iterators
I'm not sure why, but the hlist for each entry iterators were conceived
list_for_each_entry(pos, head, member)
The hlist ones were greedy and wanted an extra parameter:
hlist_for_each_entry(tpos, pos, head, member)
Why did they need an extra pos parameter? I'm not quite sure. Not only
they don't really need it, it also prevents the iterator from looking
exactly like the list iterator, which is unfortunate.
Besides the semantic patch, there was some manual work required:
- Fix up the actual hlist iterators in linux/list.h
- Fix up the declaration of other iterators based on the hlist ones.
- A very small amount of places were using the 'node' parameter, this
was modified to use 'obj->member' instead.
- Coccinelle didn't handle the hlist_for_each_entry_safe iterator
properly, so those had to be fixed up manually.
The semantic patch which is mostly the work of Peter Senna Tschudin is here:
@@
iterator name hlist_for_each_entry, hlist_for_each_entry_continue, hlist_for_each_entry_from, hlist_for_each_entry_rcu, hlist_for_each_entry_rcu_bh, hlist_for_each_entry_continue_rcu_bh, for_each_busy_worker, ax25_uid_for_each, ax25_for_each, inet_bind_bucket_for_each, sctp_for_each_hentry, sk_for_each, sk_for_each_rcu, sk_for_each_from, sk_for_each_safe, sk_for_each_bound, hlist_for_each_entry_safe, hlist_for_each_entry_continue_rcu, nr_neigh_for_each, nr_neigh_for_each_safe, nr_node_for_each, nr_node_for_each_safe, for_each_gfn_indirect_valid_sp, for_each_gfn_sp, for_each_host;
type T;
expression a,c,d,e;
identifier b;
statement S;
@@
-T b;
<+... when != b
(
hlist_for_each_entry(a,
- b,
c, d) S
|
hlist_for_each_entry_continue(a,
- b,
c) S
|
hlist_for_each_entry_from(a,
- b,
c) S
|
hlist_for_each_entry_rcu(a,
- b,
c, d) S
|
hlist_for_each_entry_rcu_bh(a,
- b,
c, d) S
|
hlist_for_each_entry_continue_rcu_bh(a,
- b,
c) S
|
for_each_busy_worker(a, c,
- b,
d) S
|
ax25_uid_for_each(a,
- b,
c) S
|
ax25_for_each(a,
- b,
c) S
|
inet_bind_bucket_for_each(a,
- b,
c) S
|
sctp_for_each_hentry(a,
- b,
c) S
|
sk_for_each(a,
- b,
c) S
|
sk_for_each_rcu(a,
- b,
c) S
|
sk_for_each_from
-(a, b)
+(a)
S
+ sk_for_each_from(a) S
|
sk_for_each_safe(a,
- b,
c, d) S
|
sk_for_each_bound(a,
- b,
c) S
|
hlist_for_each_entry_safe(a,
- b,
c, d, e) S
|
hlist_for_each_entry_continue_rcu(a,
- b,
c) S
|
nr_neigh_for_each(a,
- b,
c) S
|
nr_neigh_for_each_safe(a,
- b,
c, d) S
|
nr_node_for_each(a,
- b,
c) S
|
nr_node_for_each_safe(a,
- b,
c, d) S
|
- for_each_gfn_sp(a, c, d, b) S
+ for_each_gfn_sp(a, c, d) S
|
- for_each_gfn_indirect_valid_sp(a, c, d, b) S
+ for_each_gfn_indirect_valid_sp(a, c, d) S
|
for_each_host(a,
- b,
c) S
|
for_each_host_safe(a,
- b,
c, d) S
|
for_each_mesh_entry(a,
- b,
c, d) S
)
...+>
[akpm@linux-foundation.org: drop bogus change from net/ipv4/raw.c]
[akpm@linux-foundation.org: drop bogus hunk from net/ipv6/raw.c]
[akpm@linux-foundation.org: checkpatch fixes]
[akpm@linux-foundation.org: fix warnings]
[akpm@linux-foudnation.org: redo intrusive kvm changes]
Tested-by: Peter Senna Tschudin <peter.senna@gmail.com>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-28 09:06:00 +08:00
|
|
|
hlist_for_each_entry_safe(ri, tmp, head, hlist) {
|
2006-09-20 21:58:39 +08:00
|
|
|
if (ri->task != current)
|
|
|
|
|
/* another task is sharing our hash bucket */
|
|
|
|
|
continue;
|
|
|
|
|
|
2011-01-05 19:47:24 +08:00
|
|
|
orig_ret_address = (unsigned long) ri->ret_addr;
|
2010-11-10 17:05:58 +08:00
|
|
|
|
|
|
|
|
if (orig_ret_address != trampoline_address)
|
|
|
|
|
/*
|
|
|
|
|
* This is the real return address. Any other
|
|
|
|
|
* instances associated with this task are for
|
|
|
|
|
* other calls deeper on the call stack
|
|
|
|
|
*/
|
|
|
|
|
break;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
kretprobe_assert(ri, orig_ret_address, trampoline_address);
|
|
|
|
|
|
|
|
|
|
correct_ret_addr = ri->ret_addr;
|
hlist: drop the node parameter from iterators
I'm not sure why, but the hlist for each entry iterators were conceived
list_for_each_entry(pos, head, member)
The hlist ones were greedy and wanted an extra parameter:
hlist_for_each_entry(tpos, pos, head, member)
Why did they need an extra pos parameter? I'm not quite sure. Not only
they don't really need it, it also prevents the iterator from looking
exactly like the list iterator, which is unfortunate.
Besides the semantic patch, there was some manual work required:
- Fix up the actual hlist iterators in linux/list.h
- Fix up the declaration of other iterators based on the hlist ones.
- A very small amount of places were using the 'node' parameter, this
was modified to use 'obj->member' instead.
- Coccinelle didn't handle the hlist_for_each_entry_safe iterator
properly, so those had to be fixed up manually.
The semantic patch which is mostly the work of Peter Senna Tschudin is here:
@@
iterator name hlist_for_each_entry, hlist_for_each_entry_continue, hlist_for_each_entry_from, hlist_for_each_entry_rcu, hlist_for_each_entry_rcu_bh, hlist_for_each_entry_continue_rcu_bh, for_each_busy_worker, ax25_uid_for_each, ax25_for_each, inet_bind_bucket_for_each, sctp_for_each_hentry, sk_for_each, sk_for_each_rcu, sk_for_each_from, sk_for_each_safe, sk_for_each_bound, hlist_for_each_entry_safe, hlist_for_each_entry_continue_rcu, nr_neigh_for_each, nr_neigh_for_each_safe, nr_node_for_each, nr_node_for_each_safe, for_each_gfn_indirect_valid_sp, for_each_gfn_sp, for_each_host;
type T;
expression a,c,d,e;
identifier b;
statement S;
@@
-T b;
<+... when != b
(
hlist_for_each_entry(a,
- b,
c, d) S
|
hlist_for_each_entry_continue(a,
- b,
c) S
|
hlist_for_each_entry_from(a,
- b,
c) S
|
hlist_for_each_entry_rcu(a,
- b,
c, d) S
|
hlist_for_each_entry_rcu_bh(a,
- b,
c, d) S
|
hlist_for_each_entry_continue_rcu_bh(a,
- b,
c) S
|
for_each_busy_worker(a, c,
- b,
d) S
|
ax25_uid_for_each(a,
- b,
c) S
|
ax25_for_each(a,
- b,
c) S
|
inet_bind_bucket_for_each(a,
- b,
c) S
|
sctp_for_each_hentry(a,
- b,
c) S
|
sk_for_each(a,
- b,
c) S
|
sk_for_each_rcu(a,
- b,
c) S
|
sk_for_each_from
-(a, b)
+(a)
S
+ sk_for_each_from(a) S
|
sk_for_each_safe(a,
- b,
c, d) S
|
sk_for_each_bound(a,
- b,
c) S
|
hlist_for_each_entry_safe(a,
- b,
c, d, e) S
|
hlist_for_each_entry_continue_rcu(a,
- b,
c) S
|
nr_neigh_for_each(a,
- b,
c) S
|
nr_neigh_for_each_safe(a,
- b,
c, d) S
|
nr_node_for_each(a,
- b,
c) S
|
nr_node_for_each_safe(a,
- b,
c, d) S
|
- for_each_gfn_sp(a, c, d, b) S
+ for_each_gfn_sp(a, c, d) S
|
- for_each_gfn_indirect_valid_sp(a, c, d, b) S
+ for_each_gfn_indirect_valid_sp(a, c, d) S
|
for_each_host(a,
- b,
c) S
|
for_each_host_safe(a,
- b,
c, d) S
|
for_each_mesh_entry(a,
- b,
c, d) S
)
...+>
[akpm@linux-foundation.org: drop bogus change from net/ipv4/raw.c]
[akpm@linux-foundation.org: drop bogus hunk from net/ipv6/raw.c]
[akpm@linux-foundation.org: checkpatch fixes]
[akpm@linux-foundation.org: fix warnings]
[akpm@linux-foudnation.org: redo intrusive kvm changes]
Tested-by: Peter Senna Tschudin <peter.senna@gmail.com>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-28 09:06:00 +08:00
|
|
|
hlist_for_each_entry_safe(ri, tmp, head, hlist) {
|
2010-11-10 17:05:58 +08:00
|
|
|
if (ri->task != current)
|
|
|
|
|
/* another task is sharing our hash bucket */
|
|
|
|
|
continue;
|
2006-09-20 21:58:39 +08:00
|
|
|
|
2011-01-05 19:47:24 +08:00
|
|
|
orig_ret_address = (unsigned long) ri->ret_addr;
|
2010-11-10 17:05:58 +08:00
|
|
|
|
|
|
|
|
if (ri->rp && ri->rp->handler) {
|
|
|
|
|
ri->ret_addr = correct_ret_addr;
|
|
|
|
|
ri->rp->handler(ri, regs);
|
|
|
|
|
}
|
|
|
|
|
|
2006-10-02 17:17:35 +08:00
|
|
|
recycle_rp_inst(ri, &empty_rp);
|
2006-09-20 21:58:39 +08:00
|
|
|
|
2011-01-05 19:47:24 +08:00
|
|
|
if (orig_ret_address != trampoline_address)
|
2006-09-20 21:58:39 +08:00
|
|
|
/*
|
|
|
|
|
* This is the real return address. Any other
|
|
|
|
|
* instances associated with this task are for
|
|
|
|
|
* other calls deeper on the call stack
|
|
|
|
|
*/
|
|
|
|
|
break;
|
|
|
|
|
}
|
2010-11-10 17:05:58 +08:00
|
|
|
|
2016-01-18 19:49:44 +08:00
|
|
|
regs->psw.addr = orig_ret_address;
|
2006-09-20 21:58:39 +08:00
|
|
|
|
2008-07-25 16:46:04 +08:00
|
|
|
kretprobe_hash_unlock(current, &flags);
|
2006-09-20 21:58:39 +08:00
|
|
|
|
hlist: drop the node parameter from iterators
I'm not sure why, but the hlist for each entry iterators were conceived
list_for_each_entry(pos, head, member)
The hlist ones were greedy and wanted an extra parameter:
hlist_for_each_entry(tpos, pos, head, member)
Why did they need an extra pos parameter? I'm not quite sure. Not only
they don't really need it, it also prevents the iterator from looking
exactly like the list iterator, which is unfortunate.
Besides the semantic patch, there was some manual work required:
- Fix up the actual hlist iterators in linux/list.h
- Fix up the declaration of other iterators based on the hlist ones.
- A very small amount of places were using the 'node' parameter, this
was modified to use 'obj->member' instead.
- Coccinelle didn't handle the hlist_for_each_entry_safe iterator
properly, so those had to be fixed up manually.
The semantic patch which is mostly the work of Peter Senna Tschudin is here:
@@
iterator name hlist_for_each_entry, hlist_for_each_entry_continue, hlist_for_each_entry_from, hlist_for_each_entry_rcu, hlist_for_each_entry_rcu_bh, hlist_for_each_entry_continue_rcu_bh, for_each_busy_worker, ax25_uid_for_each, ax25_for_each, inet_bind_bucket_for_each, sctp_for_each_hentry, sk_for_each, sk_for_each_rcu, sk_for_each_from, sk_for_each_safe, sk_for_each_bound, hlist_for_each_entry_safe, hlist_for_each_entry_continue_rcu, nr_neigh_for_each, nr_neigh_for_each_safe, nr_node_for_each, nr_node_for_each_safe, for_each_gfn_indirect_valid_sp, for_each_gfn_sp, for_each_host;
type T;
expression a,c,d,e;
identifier b;
statement S;
@@
-T b;
<+... when != b
(
hlist_for_each_entry(a,
- b,
c, d) S
|
hlist_for_each_entry_continue(a,
- b,
c) S
|
hlist_for_each_entry_from(a,
- b,
c) S
|
hlist_for_each_entry_rcu(a,
- b,
c, d) S
|
hlist_for_each_entry_rcu_bh(a,
- b,
c, d) S
|
hlist_for_each_entry_continue_rcu_bh(a,
- b,
c) S
|
for_each_busy_worker(a, c,
- b,
d) S
|
ax25_uid_for_each(a,
- b,
c) S
|
ax25_for_each(a,
- b,
c) S
|
inet_bind_bucket_for_each(a,
- b,
c) S
|
sctp_for_each_hentry(a,
- b,
c) S
|
sk_for_each(a,
- b,
c) S
|
sk_for_each_rcu(a,
- b,
c) S
|
sk_for_each_from
-(a, b)
+(a)
S
+ sk_for_each_from(a) S
|
sk_for_each_safe(a,
- b,
c, d) S
|
sk_for_each_bound(a,
- b,
c) S
|
hlist_for_each_entry_safe(a,
- b,
c, d, e) S
|
hlist_for_each_entry_continue_rcu(a,
- b,
c) S
|
nr_neigh_for_each(a,
- b,
c) S
|
nr_neigh_for_each_safe(a,
- b,
c, d) S
|
nr_node_for_each(a,
- b,
c) S
|
nr_node_for_each_safe(a,
- b,
c, d) S
|
- for_each_gfn_sp(a, c, d, b) S
+ for_each_gfn_sp(a, c, d) S
|
- for_each_gfn_indirect_valid_sp(a, c, d, b) S
+ for_each_gfn_indirect_valid_sp(a, c, d) S
|
for_each_host(a,
- b,
c) S
|
for_each_host_safe(a,
- b,
c, d) S
|
for_each_mesh_entry(a,
- b,
c, d) S
)
...+>
[akpm@linux-foundation.org: drop bogus change from net/ipv4/raw.c]
[akpm@linux-foundation.org: drop bogus hunk from net/ipv6/raw.c]
[akpm@linux-foundation.org: checkpatch fixes]
[akpm@linux-foundation.org: fix warnings]
[akpm@linux-foudnation.org: redo intrusive kvm changes]
Tested-by: Peter Senna Tschudin <peter.senna@gmail.com>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-28 09:06:00 +08:00
|
|
|
hlist_for_each_entry_safe(ri, tmp, &empty_rp, hlist) {
|
2006-10-02 17:17:35 +08:00
|
|
|
hlist_del(&ri->hlist);
|
|
|
|
|
kfree(ri);
|
|
|
|
|
}
|
2006-09-20 21:58:39 +08:00
|
|
|
/*
|
|
|
|
|
* By returning a non-zero value, we are telling
|
|
|
|
|
* kprobe_handler() that we don't want the post_handler
|
|
|
|
|
* to run (and have re-enabled preemption)
|
|
|
|
|
*/
|
|
|
|
|
return 1;
|
|
|
|
|
}
|
2014-10-22 18:42:38 +08:00
|
|
|
NOKPROBE_SYMBOL(trampoline_probe_handler);
|
2006-09-20 21:58:39 +08:00
|
|
|
|
|
|
|
|
/*
|
|
|
|
|
* Called after single-stepping. p->addr is the address of the
|
|
|
|
|
* instruction whose first byte has been replaced by the "breakpoint"
|
|
|
|
|
* instruction. To avoid the SMP problems that can occur when we
|
|
|
|
|
* temporarily put back the original opcode to single-step, we
|
|
|
|
|
* single-stepped a copy of the instruction. The address of this
|
|
|
|
|
* copy is p->ainsn.insn.
|
|
|
|
|
*/
|
2014-10-22 18:42:38 +08:00
|
|
|
static void resume_execution(struct kprobe *p, struct pt_regs *regs)
|
2006-09-20 21:58:39 +08:00
|
|
|
{
|
|
|
|
|
struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
|
2016-01-18 20:12:19 +08:00
|
|
|
unsigned long ip = regs->psw.addr;
|
2014-09-22 22:37:27 +08:00
|
|
|
int fixup = probe_get_fixup_type(p->ainsn.insn);
|
2006-09-20 21:58:39 +08:00
|
|
|
|
2011-01-05 19:47:19 +08:00
|
|
|
if (fixup & FIXUP_PSW_NORMAL)
|
2011-01-05 19:47:17 +08:00
|
|
|
ip += (unsigned long) p->addr - (unsigned long) p->ainsn.insn;
|
2006-09-20 21:58:39 +08:00
|
|
|
|
2011-01-05 19:47:19 +08:00
|
|
|
if (fixup & FIXUP_BRANCH_NOT_TAKEN) {
|
2013-09-13 19:59:26 +08:00
|
|
|
int ilen = insn_length(p->ainsn.insn[0] >> 8);
|
2011-01-05 19:47:19 +08:00
|
|
|
if (ip - (unsigned long) p->ainsn.insn == ilen)
|
|
|
|
|
ip = (unsigned long) p->addr + ilen;
|
|
|
|
|
}
|
2006-09-20 21:58:39 +08:00
|
|
|
|
2011-01-05 19:47:19 +08:00
|
|
|
if (fixup & FIXUP_RETURN_REGISTER) {
|
|
|
|
|
int reg = (p->ainsn.insn[0] & 0xf0) >> 4;
|
|
|
|
|
regs->gprs[reg] += (unsigned long) p->addr -
|
|
|
|
|
(unsigned long) p->ainsn.insn;
|
|
|
|
|
}
|
2006-09-20 21:58:39 +08:00
|
|
|
|
2011-01-05 19:47:17 +08:00
|
|
|
disable_singlestep(kcb, regs, ip);
|
2006-09-20 21:58:39 +08:00
|
|
|
}
|
2014-10-22 18:42:38 +08:00
|
|
|
NOKPROBE_SYMBOL(resume_execution);
|
2006-09-20 21:58:39 +08:00
|
|
|
|
2014-10-22 18:42:38 +08:00
|
|
|
static int post_kprobe_handler(struct pt_regs *regs)
|
2006-09-20 21:58:39 +08:00
|
|
|
{
|
|
|
|
|
struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
|
2011-01-05 19:47:24 +08:00
|
|
|
struct kprobe *p = kprobe_running();
|
2006-09-20 21:58:39 +08:00
|
|
|
|
2011-01-05 19:47:24 +08:00
|
|
|
if (!p)
|
2006-09-20 21:58:39 +08:00
|
|
|
return 0;
|
|
|
|
|
|
2011-01-05 19:47:24 +08:00
|
|
|
if (kcb->kprobe_status != KPROBE_REENTER && p->post_handler) {
|
2006-09-20 21:58:39 +08:00
|
|
|
kcb->kprobe_status = KPROBE_HIT_SSDONE;
|
2011-01-05 19:47:24 +08:00
|
|
|
p->post_handler(p, regs, 0);
|
2006-09-20 21:58:39 +08:00
|
|
|
}
|
|
|
|
|
|
2011-01-05 19:47:24 +08:00
|
|
|
resume_execution(p, regs);
|
2011-01-05 19:47:20 +08:00
|
|
|
pop_kprobe(kcb);
|
2006-09-20 21:58:39 +08:00
|
|
|
preempt_enable_no_resched();
|
|
|
|
|
|
|
|
|
|
/*
|
|
|
|
|
* if somebody else is singlestepping across a probe point, psw mask
|
|
|
|
|
* will have PER set, in which case, continue the remaining processing
|
|
|
|
|
* of do_single_step, as if this is not a probe hit.
|
|
|
|
|
*/
|
2011-01-05 19:47:24 +08:00
|
|
|
if (regs->psw.mask & PSW_MASK_PER)
|
2006-09-20 21:58:39 +08:00
|
|
|
return 0;
|
|
|
|
|
|
|
|
|
|
return 1;
|
|
|
|
|
}
|
2014-10-22 18:42:38 +08:00
|
|
|
NOKPROBE_SYMBOL(post_kprobe_handler);
|
2006-09-20 21:58:39 +08:00
|
|
|
|
2014-10-22 18:42:38 +08:00
|
|
|
static int kprobe_trap_handler(struct pt_regs *regs, int trapnr)
|
2006-09-20 21:58:39 +08:00
|
|
|
{
|
|
|
|
|
struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
|
2011-01-05 19:47:24 +08:00
|
|
|
struct kprobe *p = kprobe_running();
|
2006-09-20 21:58:39 +08:00
|
|
|
const struct exception_table_entry *entry;
|
|
|
|
|
|
|
|
|
|
switch(kcb->kprobe_status) {
|
|
|
|
|
case KPROBE_HIT_SS:
|
|
|
|
|
case KPROBE_REENTER:
|
|
|
|
|
/*
|
|
|
|
|
* We are here because the instruction being single
|
|
|
|
|
* stepped caused a page fault. We reset the current
|
|
|
|
|
* kprobe and the nip points back to the probe address
|
|
|
|
|
* and allow the page fault handler to continue as a
|
|
|
|
|
* normal page fault.
|
|
|
|
|
*/
|
2011-01-05 19:47:24 +08:00
|
|
|
disable_singlestep(kcb, regs, (unsigned long) p->addr);
|
2011-01-05 19:47:20 +08:00
|
|
|
pop_kprobe(kcb);
|
2006-09-20 21:58:39 +08:00
|
|
|
preempt_enable_no_resched();
|
|
|
|
|
break;
|
|
|
|
|
case KPROBE_HIT_ACTIVE:
|
|
|
|
|
case KPROBE_HIT_SSDONE:
|
|
|
|
|
/*
|
|
|
|
|
* We increment the nmissed count for accounting,
|
2013-09-20 11:55:41 +08:00
|
|
|
* we can also use npre/npostfault count for accounting
|
2006-09-20 21:58:39 +08:00
|
|
|
* these specific fault cases.
|
|
|
|
|
*/
|
2011-01-05 19:47:24 +08:00
|
|
|
kprobes_inc_nmissed_count(p);
|
2006-09-20 21:58:39 +08:00
|
|
|
|
|
|
|
|
/*
|
|
|
|
|
* We come here because instructions in the pre/post
|
|
|
|
|
* handler caused the page_fault, this could happen
|
|
|
|
|
* if handler tries to access user space by
|
|
|
|
|
* copy_from_user(), get_user() etc. Let the
|
|
|
|
|
* user-specified handler try to fix it first.
|
|
|
|
|
*/
|
2011-01-05 19:47:24 +08:00
|
|
|
if (p->fault_handler && p->fault_handler(p, regs, trapnr))
|
2006-09-20 21:58:39 +08:00
|
|
|
return 1;
|
|
|
|
|
|
|
|
|
|
/*
|
|
|
|
|
* In case the user-specified fault handler returned
|
|
|
|
|
* zero, try to fix up.
|
|
|
|
|
*/
|
2019-02-04 04:37:20 +08:00
|
|
|
entry = s390_search_extables(regs->psw.addr);
|
2020-07-01 02:52:03 +08:00
|
|
|
if (entry && ex_handle(entry, regs))
|
2006-09-20 21:58:39 +08:00
|
|
|
return 1;
|
|
|
|
|
|
|
|
|
|
/*
|
|
|
|
|
* fixup_exception() could not handle it,
|
|
|
|
|
* Let do_page_fault() fix it.
|
|
|
|
|
*/
|
|
|
|
|
break;
|
|
|
|
|
default:
|
|
|
|
|
break;
|
|
|
|
|
}
|
|
|
|
|
return 0;
|
|
|
|
|
}
|
2014-10-22 18:42:38 +08:00
|
|
|
NOKPROBE_SYMBOL(kprobe_trap_handler);
|
2006-09-20 21:58:39 +08:00
|
|
|
|
2014-10-22 18:42:38 +08:00
|
|
|
int kprobe_fault_handler(struct pt_regs *regs, int trapnr)
|
2010-11-10 17:05:57 +08:00
|
|
|
{
|
|
|
|
|
int ret;
|
|
|
|
|
|
|
|
|
|
if (regs->psw.mask & (PSW_MASK_IO | PSW_MASK_EXT))
|
|
|
|
|
local_irq_disable();
|
|
|
|
|
ret = kprobe_trap_handler(regs, trapnr);
|
|
|
|
|
if (regs->psw.mask & (PSW_MASK_IO | PSW_MASK_EXT))
|
|
|
|
|
local_irq_restore(regs->psw.mask & ~PSW_MASK_PER);
|
|
|
|
|
return ret;
|
|
|
|
|
}
|
2014-10-22 18:42:38 +08:00
|
|
|
NOKPROBE_SYMBOL(kprobe_fault_handler);
|
2010-11-10 17:05:57 +08:00
|
|
|
|
2006-09-20 21:58:39 +08:00
|
|
|
/*
|
|
|
|
|
* Wrapper routine to for handling exceptions.
|
|
|
|
|
*/
|
2014-10-22 18:42:38 +08:00
|
|
|
int kprobe_exceptions_notify(struct notifier_block *self,
|
|
|
|
|
unsigned long val, void *data)
|
2006-09-20 21:58:39 +08:00
|
|
|
{
|
2011-01-05 19:47:24 +08:00
|
|
|
struct die_args *args = (struct die_args *) data;
|
2010-11-10 17:05:57 +08:00
|
|
|
struct pt_regs *regs = args->regs;
|
2006-09-20 21:58:39 +08:00
|
|
|
int ret = NOTIFY_DONE;
|
|
|
|
|
|
2010-11-10 17:05:57 +08:00
|
|
|
if (regs->psw.mask & (PSW_MASK_IO | PSW_MASK_EXT))
|
|
|
|
|
local_irq_disable();
|
|
|
|
|
|
2006-09-20 21:58:39 +08:00
|
|
|
switch (val) {
|
|
|
|
|
case DIE_BPT:
|
2011-01-05 19:47:24 +08:00
|
|
|
if (kprobe_handler(regs))
|
2006-09-20 21:58:39 +08:00
|
|
|
ret = NOTIFY_STOP;
|
|
|
|
|
break;
|
|
|
|
|
case DIE_SSTEP:
|
2011-01-05 19:47:24 +08:00
|
|
|
if (post_kprobe_handler(regs))
|
2006-09-20 21:58:39 +08:00
|
|
|
ret = NOTIFY_STOP;
|
|
|
|
|
break;
|
|
|
|
|
case DIE_TRAP:
|
2010-11-10 17:05:57 +08:00
|
|
|
if (!preemptible() && kprobe_running() &&
|
2011-01-05 19:47:24 +08:00
|
|
|
kprobe_trap_handler(regs, args->trapnr))
|
2006-09-20 21:58:39 +08:00
|
|
|
ret = NOTIFY_STOP;
|
|
|
|
|
break;
|
|
|
|
|
default:
|
|
|
|
|
break;
|
|
|
|
|
}
|
2010-11-10 17:05:57 +08:00
|
|
|
|
|
|
|
|
if (regs->psw.mask & (PSW_MASK_IO | PSW_MASK_EXT))
|
|
|
|
|
local_irq_restore(regs->psw.mask & ~PSW_MASK_PER);
|
|
|
|
|
|
2006-09-20 21:58:39 +08:00
|
|
|
return ret;
|
|
|
|
|
}
|
2014-10-22 18:42:38 +08:00
|
|
|
NOKPROBE_SYMBOL(kprobe_exceptions_notify);
|
2006-09-20 21:58:39 +08:00
|
|
|
|
2011-01-05 19:47:24 +08:00
|
|
|
static struct kprobe trampoline = {
|
|
|
|
|
.addr = (kprobe_opcode_t *) &kretprobe_trampoline,
|
2006-09-20 21:58:39 +08:00
|
|
|
.pre_handler = trampoline_probe_handler
|
|
|
|
|
};
|
|
|
|
|
|
|
|
|
|
int __init arch_init_kprobes(void)
|
|
|
|
|
{
|
2011-01-05 19:47:24 +08:00
|
|
|
return register_kprobe(&trampoline);
|
2006-09-20 21:58:39 +08:00
|
|
|
}
|
2007-05-08 15:34:16 +08:00
|
|
|
|
2014-10-22 18:42:38 +08:00
|
|
|
int arch_trampoline_kprobe(struct kprobe *p)
|
2007-05-08 15:34:16 +08:00
|
|
|
{
|
2011-01-05 19:47:24 +08:00
|
|
|
return p->addr == (kprobe_opcode_t *) &kretprobe_trampoline;
|
2007-05-08 15:34:16 +08:00
|
|
|
}
|
2014-10-22 18:42:38 +08:00
|
|
|
NOKPROBE_SYMBOL(arch_trampoline_kprobe);
|