Commit Graph

19142 Commits

Author SHA1 Message Date
Ingo Molnar
10b0256496 Merge branch 'perf/kprobes' into perf/core
Conflicts:
	arch/x86/kernel/traps.c

The kprobes enhancements are fully cooked, ship them upstream.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-06-05 12:26:50 +02:00
Ingo Molnar
c56d34064b Merge branch 'perf/uprobes' into perf/core
These bits from Oleg are fully cooked, ship them to Linus.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-06-05 12:26:27 +02:00
Stephane Eranian
722e76e60f fix Haswell precise store data source encoding
This patch fixes a bug in  precise_store_data_hsw() whereby
it would set the data source memory level to the wrong value.

As per the the SDM Vol 3b Table 18-41 (Layout of Data Linear
Address Information in PEBS Record), when status bit 0 is set
this is a L1 hit, otherwise this is a L1 miss.

This patch encodes the memory level according to the specification.

In V2, we added the filtering on the store events.
Only the following events produce L1 information:
 * MEM_UOPS_RETIRED.STLB_MISS_STORES
 * MEM_UOPS_RETIRED.LOCK_STORES
 * MEM_UOPS_RETIRED.SPLIT_STORES
 * MEM_UOPS_RETIRED.ALL_STORES

Cc: mingo@elte.hu
Cc: acme@ghostprotocols.net
Cc: jolsa@redhat.com
Cc: jmario@redhat.com
Cc: ak@linux.intel.com
Tested-and-Reviewed-by: Don Zickus <dzickus@redhat.com>
Signed-off-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20140515155644.GA3884@quad
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-05-19 21:52:59 +09:00
Oleg Nesterov
b02ef20a9f uprobes/x86: Fix the wrong ->si_addr when xol triggers a trap
If the probed insn triggers a trap, ->si_addr = regs->ip is technically
correct, but this is not what the signal handler wants; we need to pass
the address of the probed insn, not the address of xol slot.

Add the new arch-agnostic helper, uprobe_get_trap_addr(), and change
fill_trap_info() and math_error() to use it. !CONFIG_UPROBES case in
uprobes.h uses a macro to avoid include hell and ensure that it can be
compiled even if an architecture doesn't define instruction_pointer().

Test-case:

	#include <signal.h>
	#include <stdio.h>
	#include <unistd.h>

	extern void probe_div(void);

	void sigh(int sig, siginfo_t *info, void *c)
	{
		int passed = (info->si_addr == probe_div);
		printf(passed ? "PASS\n" : "FAIL\n");
		_exit(!passed);
	}

	int main(void)
	{
		struct sigaction sa = {
			.sa_sigaction	= sigh,
			.sa_flags	= SA_SIGINFO,
		};

		sigaction(SIGFPE, &sa, NULL);

		asm (
			"xor %ecx,%ecx\n"
			".globl probe_div; probe_div:\n"
			"idiv %ecx\n"
		);

		return 0;
	}

it fails if probe_div() is probed.

Note: show_unhandled_signals users should probably use this helper too,
but we need to cleanup them first.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
2014-05-14 13:57:28 +02:00
Oleg Nesterov
0eb14833d5 x86/traps: Kill DO_ERROR_INFO()
Now that DO_ERROR_INFO() doesn't differ from DO_ERROR() we can remove
it and use DO_ERROR() instead.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
2014-05-14 13:57:28 +02:00
Oleg Nesterov
1c326c4dfe x86/traps: Shift fill_trap_info() from DO_ERROR_INFO() to do_error_trap()
Move the callsite of fill_trap_info() into do_error_trap() and remove
the "siginfo_t *info" argument.

This obviously breaks DO_ERROR() which passed info == NULL, we simply
change fill_trap_info() to return "siginfo_t *" and add the "default"
case which returns SEND_SIG_PRIV.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
2014-05-14 13:57:27 +02:00
Oleg Nesterov
958d3d7298 x86/traps: Introduce fill_trap_info(), simplify DO_ERROR_INFO()
Extract the fill-siginfo code from DO_ERROR_INFO() into the new helper,
fill_trap_info().

It can calculate si_code and si_addr looking at trapnr, so we can remove
these arguments from DO_ERROR_INFO() and simplify the source code. The
generated code is the same, __builtin_constant_p(trapnr) == T.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
2014-05-14 13:57:27 +02:00
Oleg Nesterov
dff0796e53 x86/traps: Introduce do_error_trap()
Move the common code from DO_ERROR() and DO_ERROR_INFO() into the new
helper, do_error_trap(). This simplifies define's and shaves 527 bytes
from traps.o.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
2014-05-14 13:57:27 +02:00
Oleg Nesterov
38cad57be9 x86/traps: Use SEND_SIG_PRIV instead of force_sig()
force_sig() is just force_sig_info(SEND_SIG_PRIV). Imho it should die,
we have too many ugly "send signal" helpers.

And do_trap() looks just ugly because it uses force_sig_info() or
force_sig() depending on info != NULL.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
2014-05-14 13:57:26 +02:00
Oleg Nesterov
5e1b05beec x86/traps: Make math_error() static
Trivial, make math_error() static.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
2014-05-14 13:57:26 +02:00
Denys Vlasenko
1ea30fb645 uprobes/x86: Fix scratch register selection for rip-relative fixups
Before this patch, instructions such as div, mul, shifts with count
in CL, cmpxchg are mishandled.

This patch adds vex prefix handling. In particular, it avoids colliding
with register operand encoded in vex.vvvv field.

Since we need to avoid two possible register operands, the selection of
scratch register needs to be from at least three registers.

After looking through a lot of CPU docs, it looks like the safest choice
is SI,DI,BX. Selecting BX needs care to not collide with implicit use of
BX by cmpxchg8b.

Test-case:

	#include <stdio.h>

	static const char *const pass[] = { "FAIL", "pass" };

	long two = 2;
	void test1(void)
	{
		long ax = 0, dx = 0;
		asm volatile("\n"
	"			xor	%%edx,%%edx\n"
	"			lea	2(%%edx),%%eax\n"
	// We divide 2 by 2. Result (in eax) should be 1:
	"	probe1:		.globl	probe1\n"
	"			divl	two(%%rip)\n"
	// If we have a bug (eax mangled on entry) the result will be 2,
	// because eax gets restored by probe machinery.
		: "=a" (ax), "=d" (dx) /*out*/
		: "0" (ax), "1" (dx) /*in*/
		: "memory" /*clobber*/
		);
		dprintf(2, "%s: %s\n", __func__,
			pass[ax == 1]
		);
	}

	long val2 = 0;
	void test2(void)
	{
		long old_val = val2;
		long ax = 0, dx = 0;
		asm volatile("\n"
	"			mov	val2,%%eax\n"     // eax := val2
	"			lea	1(%%eax),%%edx\n" // edx := eax+1
	// eax is equal to val2. cmpxchg should store edx to val2:
	"	probe2:		.globl  probe2\n"
	"			cmpxchg %%edx,val2(%%rip)\n"
	// If we have a bug (eax mangled on entry), val2 will stay unchanged
		: "=a" (ax), "=d" (dx) /*out*/
		: "0" (ax), "1" (dx) /*in*/
		: "memory" /*clobber*/
		);
		dprintf(2, "%s: %s\n", __func__,
			pass[val2 == old_val + 1]
		);
	}

	long val3[2] = {0,0};
	void test3(void)
	{
		long old_val = val3[0];
		long ax = 0, dx = 0;
		asm volatile("\n"
	"			mov	val3,%%eax\n"  // edx:eax := val3
	"			mov	val3+4,%%edx\n"
	"			mov	%%eax,%%ebx\n" // ecx:ebx := edx:eax + 1
	"			mov	%%edx,%%ecx\n"
	"			add	$1,%%ebx\n"
	"			adc	$0,%%ecx\n"
	// edx:eax is equal to val3. cmpxchg8b should store ecx:ebx to val3:
	"	probe3:		.globl  probe3\n"
	"			cmpxchg8b val3(%%rip)\n"
	// If we have a bug (edx:eax mangled on entry), val3 will stay unchanged.
	// If ecx:edx in mangled, val3 will get wrong value.
		: "=a" (ax), "=d" (dx) /*out*/
		: "0" (ax), "1" (dx) /*in*/
		: "cx", "bx", "memory" /*clobber*/
		);
		dprintf(2, "%s: %s\n", __func__,
			pass[val3[0] == old_val + 1 && val3[1] == 0]
		);
	}

	int main(int argc, char **argv)
	{
		test1();
		test2();
		test3();
		return 0;
	}

Before this change all tests fail if probe{1,2,3} are probed.

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Reviewed-by: Jim Keniston <jkenisto@us.ibm.com>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
2014-05-14 13:57:25 +02:00
Denys Vlasenko
50204c6f6d uprobes/x86: Simplify rip-relative handling
It is possible to replace rip-relative addressing mode with addressing
mode of the same length: (reg+disp32). This eliminates the need to fix
up immediate and correct for changing instruction length.

And we can kill arch_uprobe->def.riprel_target.

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Reviewed-by: Jim Keniston <jkenisto@us.ibm.com>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
2014-05-14 13:57:25 +02:00
Ingo Molnar
37b16beaa9 Merge branch 'perf/urgent' into perf/core, to avoid conflicts
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-05-07 13:39:22 +02:00
Yan, Zheng
a4b4f11b27 perf/x86/intel: Fix Silvermont's event constraints
Event 0x013c is not the same as fixed counter2, remove it from
Silvermont's event constraints.

Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1398755081-12471-1-git-send-email-zheng.z.yan@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-05-07 11:33:16 +02:00
Linus Torvalds
0384dcae2b Merge branch 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq fixes from Thomas Gleixner:
 "This udpate delivers:

   - A fix for dynamic interrupt allocation on x86 which is required to
     exclude the GSI interrupts from the dynamic allocatable range.

     This was detected with the newfangled tablet SoCs which have GPIOs
     and therefor allocate a range of interrupts.  The MSI allocations
     already excluded the GSI range, so we never noticed before.

   - The last missing set_irq_affinity() repair, which was delayed due
     to testing issues

   - A few bug fixes for the armada SoC interrupt controller

   - A memory allocation fix for the TI crossbar interrupt controller

   - A trivial kernel-doc warning fix"

* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  irqchip: irq-crossbar: Not allocating enough memory
  irqchip: armanda: Sanitize set_irq_affinity()
  genirq: x86: Ensure that dynamic irq allocation does not conflict
  linux/interrupt.h: fix new kernel-doc warnings
  irqchip: armada-370-xp: Fix releasing of MSIs
  irqchip: armada-370-xp: implement the ->check_device() msi_chip operation
  irqchip: armada-370-xp: fix invalid cast of signed value into unsigned variable
2014-05-03 08:32:48 -07:00
Linus Torvalds
0845e11c2a Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Peter Anvin:
 "Two very small changes: one fix for the vSMP Foundation platform, and
  one to help LLVM not choke on options it doesn't understand (although
  it probably should)"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/vsmp: Fix irq routing
  x86: LLVMLinux: Wrap -mno-80387 with cc-option
2014-05-02 14:04:52 -07:00
Linus Torvalds
e7e6d2a4a1 - Fix for a Haswell regression in nested virtualization, introduced during
the merge window.
 
 - A fix from Oleg to async page faults.
 
 - A bunch of small ARM changes.
 
 - A trivial patch to use the new MSI-X API introduced during the merge
 window.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM fixes from Paolo Bonzini:
 - Fix for a Haswell regression in nested virtualization, introduced
   during the merge window.
 - A fix from Oleg to async page faults.
 - A bunch of small ARM changes.
 - A trivial patch to use the new MSI-X API introduced during the merge
   window.

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: ARM: vgic: Fix the overlap check action about setting the GICD & GICC base address.
  KVM: arm/arm64: vgic: fix GICD_ICFGR register accesses
  KVM: async_pf: mm->mm_users can not pin apf->mm
  KVM: ARM: vgic: Fix sgi dispatch problem
  MAINTAINERS: co-maintainance of KVM/{arm,arm64}
  arm: KVM: fix possible misalignment of PGDs and bounce page
  KVM: x86: Check for host supported fields in shadow vmcs
  kvm: Use pci_enable_msix_exact() instead of pci_enable_msix()
  ARM: KVM: disable KVM in Kconfig on big-endian systems
2014-05-02 09:26:09 -07:00
Oleg Nesterov
c90a695012 uprobes/x86: Simplify riprel_{pre,post}_xol() and make them similar
Ignoring the "correction" logic riprel_pre_xol() and riprel_post_xol()
are very similar but look quite differently.

1. Add the "UPROBE_FIX_RIP_AX | UPROBE_FIX_RIP_CX" check at the start
   of riprel_pre_xol(), like the same check in riprel_post_xol().

2. Add the trivial scratch_reg() helper which returns the address of
   scratch register pre_xol/post_xol need to change.

3. Change these functions to use the new helper and avoid copy-and-paste
   under if/else branches.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
2014-04-30 19:10:41 +02:00
Oleg Nesterov
7f55e82bac uprobes/x86: Kill the "autask" arg of riprel_pre_xol()
default_pre_xol_op() passes &current->utask->autask to riprel_pre_xol()
and this is just ugly because it still needs to load current->utask to
read ->vaddr.

Remove this argument, change riprel_pre_xol() to use current->utask.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
2014-04-30 19:10:41 +02:00
Oleg Nesterov
1475ee7fad uprobes/x86: Rename *riprel* helpers to make the naming consistent
handle_riprel_insn(), pre_xol_rip_insn() and handle_riprel_post_xol()
look confusing and inconsistent. Rename them into riprel_analyze(),
riprel_pre_xol(), and riprel_post_xol() respectively.

No changes in compiled code.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
2014-04-30 19:10:41 +02:00
Oleg Nesterov
83cd591485 uprobes/x86: Cleanup the usage of UPROBE_FIX_IP/UPROBE_FIX_CALL
Now that UPROBE_FIX_IP/UPROBE_FIX_CALL are mutually exclusive we can
use a single "fix_ip_or_call" enum instead of 2 fix_* booleans. This
way the logic looks more understandable and clean to me.

While at it, join "case 0xea" with other "ip is correct" ret/lret cases.
Also change default_post_xol_op() to use "else if" for the same reason.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
2014-04-30 19:10:40 +02:00
Oleg Nesterov
1dc76e6eac uprobes/x86: Kill adjust_ret_addr(), simplify UPROBE_FIX_CALL logic
The only insn which could have both UPROBE_FIX_IP and UPROBE_FIX_CALL
was 0xe8 "call relative", and now it is handled by branch_xol_ops.

So we can change default_post_xol_op(UPROBE_FIX_CALL) to simply push
the address of next insn == utask->vaddr + insn.length, just we need
to record insn.length into the new auprobe->def.ilen member.

Note: if/when we teach branch_xol_ops to support jcxz/loopz we can
remove the "correction" logic, UPROBE_FIX_IP can use the same address.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
2014-04-30 19:10:39 +02:00
Oleg Nesterov
2b82cadffc uprobes/x86: Introduce push_ret_address()
Extract the "push return address" code from branch_emulate_op() into
the new simple helper, push_ret_address(). It will have more users.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
2014-04-30 19:10:38 +02:00
Oleg Nesterov
78d9af4cd3 uprobes/x86: Cleanup the usage of arch_uprobe->def.fixups, make it u8
handle_riprel_insn() assumes that nobody else could modify ->fixups
before. This is correct but fragile, change it to use "|=".

Also make ->fixups u8, we are going to add the new members into the
union. It is not clear why UPROBE_FIX_RIP_.X lived in the upper byte,
redefine them so that they can fit into u8.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
2014-04-30 19:10:38 +02:00
Oleg Nesterov
97aa5cddbe uprobes/x86: Move default_xol_ops's data into arch_uprobe->def
Finally we can move arch_uprobe->fixups/rip_rela_target_address
into the new "def" struct and place this struct in the union, they
are only used by default_xol_ops paths.

The patch also renames rip_rela_target_address to riprel_target just
to make this name shorter.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Jim Keniston <jkenisto@us.ibm.com>
2014-04-30 19:10:37 +02:00
Oleg Nesterov
220ef8dc9a uprobes/x86: Move UPROBE_FIX_SETF logic from arch_uprobe_post_xol() to default_post_xol_op()
UPROBE_FIX_SETF is only needed to handle "popf" correctly but it is
processed by the generic arch_uprobe_post_xol() code. This doesn't
allows us to make ->fixups private for default_xol_ops.

1 Change default_post_xol_op(UPROBE_FIX_SETF) to set ->saved_tf = T.

   "popf" always reads the flags from stack, it doesn't matter if TF
   was set or not before single-step. Ignoring the naming, this is
   even more logical, "saved_tf" means "owned by application" and we
   do not own this flag after "popf".

2. Change arch_uprobe_post_xol() to save ->saved_tf into the local
   "bool send_sigtrap" before ->post_xol().

3. Change arch_uprobe_post_xol() to ignore UPROBE_FIX_SETF and just
   check ->saved_tf after ->post_xol().

With this patch ->fixups and ->rip_rela_target_address are only used
by default_xol_ops hooks, we are ready to remove them from the common
part of arch_uprobe.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Jim Keniston <jkenisto@us.ibm.com>
2014-04-30 19:10:37 +02:00
Oleg Nesterov
6ded5f3848 uprobes/x86: Don't use arch_uprobe_abort_xol() in arch_uprobe_post_xol()
014940bad8 "uprobes/x86: Send SIGILL if arch_uprobe_post_xol() fails"
changed arch_uprobe_post_xol() to use arch_uprobe_abort_xol() if ->post_xol
fails. This was correct and helped to avoid the additional complications,
we need to clear X86_EFLAGS_TF in this case.

However, now that we have uprobe_xol_ops->abort() hook it would be better
to avoid arch_uprobe_abort_xol() here. ->post_xol() should likely do what
->abort() does anyway, we should not do the same work twice. Currently only
handle_riprel_post_xol() can be called twice, this is unnecessary but safe.
Still this is not clean and can lead to the problems in future.

Change arch_uprobe_post_xol() to clear X86_EFLAGS_TF and restore ->ip by
hand and avoid arch_uprobe_abort_xol(). This temporary uglifies the usage
of autask.saved_tf, we will cleanup this later.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Jim Keniston <jkenisto@us.ibm.com>
2014-04-30 19:10:37 +02:00
Oleg Nesterov
588fbd613c uprobes/x86: Introduce uprobe_xol_ops->abort() and default_abort_op()
arch_uprobe_abort_xol() calls handle_riprel_post_xol() even if
auprobe->ops != default_xol_ops. This is fine correctness wise, only
default_pre_xol_op() can set UPROBE_FIX_RIP_AX|UPROBE_FIX_RIP_CX and
otherwise handle_riprel_post_xol() is nop.

But this doesn't look clean and this doesn't allow us to move ->fixups
into the union in arch_uprobe. Move this handle_riprel_post_xol() call
into the new default_abort_op() hook and change arch_uprobe_abort_xol()
accordingly.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Jim Keniston <jkenisto@us.ibm.com>
2014-04-30 19:10:36 +02:00
Oleg Nesterov
dd91016dfc uprobes/x86: Don't change the task's state if ->pre_xol() fails
Currently this doesn't matter, the only ->pre_xol() hook can't fail,
but we need to fix arch_uprobe_pre_xol() anyway. If ->pre_xol() fails
we should not change regs->ip/flags, we should just return the error
to make restart actually possible.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Jim Keniston <jkenisto@us.ibm.com>
2014-04-30 19:10:36 +02:00
Oleg Nesterov
b24dc8dace uprobes/x86: Fix is_64bit_mm() with CONFIG_X86_X32
is_64bit_mm() assumes that mm->context.ia32_compat means the 32-bit
instruction set, this is not true if the task is TIF_X32.

Change set_personality_ia32() to initialize mm->context.ia32_compat
by TIF_X32 or TIF_IA32 instead of 1. This allows to fix is_64bit_mm()
without affecting other users, they all treat ia32_compat as "bool".

TIF_ in ->ia32_compat looks a bit strange, but this is grep-friendly
and avoids the new define's.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Jim Keniston <jkenisto@us.ibm.com>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
2014-04-30 19:10:35 +02:00
Oleg Nesterov
8dbacad93a uprobes/x86: Make good_insns_* depend on CONFIG_X86_*
Add the suitable ifdef's around good_insns_* arrays. We do not want
to add the ugly ifdef's into their only user, uprobe_init_insn(), so
the "#else" branch simply defines them as NULL. This doesn't generate
the extra code, gcc is smart enough, although the code is fine even if
it could not detect that (without CONFIG_IA32_EMULATION) is_64bit_mm()
is __builtin_constant_p().

The patch looks more complicated because it also moves good_insns_64
up close to good_insns_32.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Jim Keniston <jkenisto@us.ibm.com>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
2014-04-30 19:10:35 +02:00
Oleg Nesterov
ff261964cf uprobes/x86: Shift "insn_complete" from branch_setup_xol_ops() to uprobe_init_insn()
Change uprobe_init_insn() to make insn_complete() == T, this makes
other insn_get_*() calls unnecessary.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Jim Keniston <jkenisto@us.ibm.com>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
2014-04-30 19:10:34 +02:00
Oleg Nesterov
2ae1f49ae1 uprobes/x86: Add is_64bit_mm(), kill validate_insn_bits()
1. Extract the ->ia32_compat check from 64bit validate_insn_bits()
   into the new helper, is_64bit_mm(), it will have more users.

   TODO: this checks is actually wrong if mm owner is X32 task,
   we need another fix which changes set_personality_ia32().

   TODO: even worse, the whole 64-or-32-bit logic is very broken
   and the fix is not simple, we need the nontrivial changes in
   the core uprobes code.

2. Kill validate_insn_bits() and change its single caller to use
   uprobe_init_insn(is_64bit_mm(mm).

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Jim Keniston <jkenisto@us.ibm.com>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
2014-04-30 19:10:33 +02:00
Oleg Nesterov
73175d0d19 uprobes/x86: Add uprobe_init_insn(), kill validate_insn_{32,64}bits()
validate_insn_32bits() and validate_insn_64bits() are very similar,
turn them into the single uprobe_init_insn() which has the additional
"bool x86_64" argument which can be passed to insn_init() and used to
choose between good_insns_64/good_insns_32.

Also kill UPROBE_FIX_NONE, it has no users.

Note: the current code doesn't use ifdef's consistently, good_insns_64
depends on CONFIG_X86_64 but good_insns_32 is unconditional. This patch
removes ifdef around good_insns_64, we will add it back later along with
the similar one for good_insns_32.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Jim Keniston <jkenisto@us.ibm.com>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
2014-04-30 19:10:33 +02:00
Denys Vlasenko
250bbd12c2 uprobes/x86: Refuse to attach uprobe to "word-sized" branch insns
All branch insns on x86 can be prefixed with the operand-size
override prefix, 0x66. It was only ever useful for performing
jumps to 32-bit offsets in 16-bit code segments.

In 32-bit code, such instructions are useless since
they cause IP truncation to 16 bits, and in case of call insns,
they save only 16 bits of return address and misalign
the stack pointer as a "bonus".

In 64-bit code, such instructions are treated differently by Intel
and AMD CPUs: Intel ignores the prefix altogether,
AMD treats them the same as in 32-bit mode.

Before this patch, the emulation code would execute
the instructions as if they have no 0x66 prefix.

With this patch, we refuse to attach uprobes to such insns.

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Acked-by: Jim Keniston <jkenisto@us.ibm.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
2014-04-30 19:10:33 +02:00
Thomas Gleixner
62a08ae2a5 genirq: x86: Ensure that dynamic irq allocation does not conflict
On x86 the allocation of irq descriptors may allocate interrupts which
are in the range of the GSI interrupts. That's wrong as those
interrupts are hardwired and we don't have the irq domain translation
like PPC. So one of these interrupts can be hooked up later to one of
the devices which are hard wired to it and the io_apic init code for
that particular interrupt line happily reuses that descriptor with a
completely different configuration so hell breaks lose.

Inside x86 we allocate dynamic interrupts from above nr_gsi_irqs,
except for a few usage sites which have not yet blown up in our face
for whatever reason. But for drivers which need an irq range, like the
GPIO drivers, we have no limit in place and we don't want to expose
such a detail to a driver.

To cure this introduce a function which an architecture can implement
to impose a lower bound on the dynamic interrupt allocations.

Implement it for x86 and set the lower bound to nr_gsi_irqs, which is
the end of the hardwired interrupt space, so all dynamic allocations
happen above.

That not only allows the GPIO driver to work sanely, it also protects
the bogus callsites of create_irq_nr() in hpet, uv, irq_remapping and
htirq code. They need to be cleaned up as well, but that's a separate
issue.

Reported-by: Jin Yao <yao.jin@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Cc: Mathias Nyman <mathias.nyman@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Grant Likely <grant.likely@linaro.org>
Cc: H. Peter Anvin <hpa@linux.intel.com>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Krogerus Heikki <heikki.krogerus@intel.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Link: http://lkml.kernel.org/r/alpine.DEB.2.02.1404241617360.28206@ionos.tec.linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-04-28 12:20:00 +02:00
Bandan Das
fe2b201b3b KVM: x86: Check for host supported fields in shadow vmcs
We track shadow vmcs fields through two static lists,
one for read only and another for r/w fields. However, with
addition of new vmcs fields, not all fields may be supported on
all hosts. If so, copy_vmcs12_to_shadow() trying to vmwrite on
unsupported hosts will result in a vmwrite error. For example, commit
36be0b9deb introduced GUEST_BNDCFGS, which is not supported
by all processors. Filter out host unsupported fields before
letting guests use shadow vmcs

Signed-off-by: Bandan Das <bsd@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-04-28 11:14:51 +02:00
Oren Twaig
39025ba382 x86/vsmp: Fix irq routing
Correct IRQ routing in case a vSMP box is detected
but the  Interrupt Routing Comply (IRC) value is set to
"comply", which leads to incorrect IRQ routing.

Before the patch:

When a vSMP box was detected and IRC was set to "comply",
users (and the kernel) couldn't effectively set the
destination of the IRQs. This is because the hook inside
vsmp_64.c always setup all CPUs as the IRQ destination using
cpumask_setall() as the return value for IRQ allocation mask.
Later, this "overrided" mask caused the kernel to set the IRQ
destination to the lowest online CPU in the mask (CPU0 usually).

After the patch:

When the IRC is set to "comply", users (and the kernel) can control
the destination of the IRQs as we will not be changing the
default "apic->vector_allocation_domain".

Signed-off-by: Oren Twaig <oren@scalemp.com>
Acked-by: Shai Fultheim <shai@scalemp.com>
Link: http://lkml.kernel.org/r/1398669697-2123-1-git-send-email-oren@scalemp.com
[ Minor readability edits. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-04-28 09:27:34 +02:00
Ingo Molnar
42ebd27bcb Merge branch 'perf/urgent' into perf/core, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-04-25 10:04:22 +02:00
Masami Hiramatsu
9326638cbe kprobes, x86: Use NOKPROBE_SYMBOL() instead of __kprobes annotation
Use NOKPROBE_SYMBOL macro for protecting functions
from kprobes instead of __kprobes annotation under
arch/x86.

This applies nokprobe_inline annotation for some cases,
because NOKPROBE_SYMBOL() will inhibit inlining by
referring the symbol address.

This just folds a bunch of previous NOKPROBE_SYMBOL()
cleanup patches for x86 to one patch.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Link: http://lkml.kernel.org/r/20140417081814.26341.51656.stgit@ltc230.yrl.intra.hitachi.co.jp
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Fernando Luis Vázquez Cao <fernando_b1@lab.ntt.co.jp>
Cc: Gleb Natapov <gleb@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Jonathan Lebon <jlebon@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Matt Fleming <matt.fleming@intel.com>
Cc: Michel Lespinasse <walken@google.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Seiji Aguchi <seiji.aguchi@hds.com>
Cc: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Vineet Gupta <vgupta@synopsys.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-04-24 10:26:38 +02:00
Masami Hiramatsu
9c54b6164e kprobes, x86: Allow kprobes on text_poke/hw_breakpoint
Allow kprobes on text_poke/hw_breakpoint because
those are not related to the critical int3-debug
recursive path of kprobes at this moment.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Reviewed-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Fengguang Wu <fengguang.wu@intel.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Link: http://lkml.kernel.org/r/20140417081807.26341.73219.stgit@ltc230.yrl.intra.hitachi.co.jp
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-04-24 10:03:02 +02:00
Masami Hiramatsu
7ec8a97a99 kprobes/x86: Allow probe on some kprobe preparation functions
There is no need to prohibit probing on the functions
used in preparation phase. Those are safely probed because
those are not invoked from breakpoint/fault/debug handlers,
there is no chance to cause recursive exceptions.

Following functions are now removed from the kprobes blacklist:

	can_boost
	can_probe
	can_optimize
	is_IF_modifier
	__copy_instruction
	copy_optimized_instructions
	arch_copy_kprobe
	arch_prepare_kprobe
	arch_arm_kprobe
	arch_disarm_kprobe
	arch_remove_kprobe
	arch_trampoline_kprobe
	arch_prepare_kprobe_ftrace
	arch_prepare_optimized_kprobe
	arch_check_optimized_kprobe
	arch_within_optimized_kprobe
	__arch_remove_optimized_kprobe
	arch_remove_optimized_kprobe
	arch_optimize_kprobes
	arch_unoptimize_kprobe

I tested those functions by putting kprobes on all
instructions in the functions with the bash script
I sent to LKML. See:

  https://lkml.org/lkml/2014/3/27/33

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Jonathan Lebon <jlebon@redhat.com>
Link: http://lkml.kernel.org/r/20140417081747.26341.36065.stgit@ltc230.yrl.intra.hitachi.co.jp
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-04-24 10:03:01 +02:00
Masami Hiramatsu
ecd50f714c kprobes, x86: Call exception_enter after kprobes handled
Move exception_enter() call after kprobes handler
is done. Since the exception_enter() involves
many other functions (like printk), it can cause
recursive int3/break loop when kprobes probe such
functions.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Reviewed-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Kees Cook <keescook@chromium.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Seiji Aguchi <seiji.aguchi@hds.com>
Link: http://lkml.kernel.org/r/20140417081740.26341.10894.stgit@ltc230.yrl.intra.hitachi.co.jp
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-04-24 10:03:00 +02:00
Masami Hiramatsu
6f6343f53d kprobes/x86: Call exception handlers directly from do_int3/do_debug
To avoid a kernel crash by probing on lockdep code, call
kprobe_int3_handler() and kprobe_debug_handler()(which was
formerly called post_kprobe_handler()) directly from
do_int3 and do_debug.

Currently kprobes uses notify_die() to hook the int3/debug
exceptoins. Since there is a locking code in notify_die,
the lockdep code can be invoked. And because the lockdep
involves printk() related things, theoretically, we need to
prohibit probing on such code, which means much longer blacklist
we'll have. Instead, hooking the int3/debug for kprobes before
notify_die() can avoid this problem.

Anyway, most of the int3 handlers in the kernel are already
called from do_int3 directly, e.g. ftrace_int3_handler,
poke_int3_handler, kgdb_ll_trap. Actually only
kprobe_exceptions_notify is on the notifier_call_chain.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Reviewed-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Jonathan Lebon <jlebon@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Seiji Aguchi <seiji.aguchi@hds.com>
Link: http://lkml.kernel.org/r/20140417081733.26341.24423.stgit@ltc230.yrl.intra.hitachi.co.jp
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-04-24 10:02:59 +02:00
Masami Hiramatsu
98def1dedd kprobes, x86: Prohibit probing on thunk functions and restore
thunk/restore functions are also used for tracing irqoff etc.
and those are involved in kprobe's exception handling.
Prohibit probing on them to avoid kernel crash.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Reviewed-by: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20140417081726.26341.3872.stgit@ltc230.yrl.intra.hitachi.co.jp
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-04-24 10:02:58 +02:00
Masami Hiramatsu
8027197220 kprobes, x86: Prohibit probing on native_set_debugreg()/load_idt()
Since the kprobes uses do_debug for single stepping,
functions called from do_debug() before notify_die() must not
be probed.

And also native_load_idt() is called from paranoid_exit when
returning int3, this also must not be probed.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Reviewed-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Alok Kataria <akataria@vmware.com>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: virtualization@lists.linux-foundation.org
Link: http://lkml.kernel.org/r/20140417081719.26341.65542.stgit@ltc230.yrl.intra.hitachi.co.jp
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-04-24 10:02:58 +02:00
Masami Hiramatsu
0f46efeb44 kprobes, x86: Prohibit probing on debug_stack_*()
Prohibit probing on debug_stack_reset and debug_stack_set_zero.
Since the both functions are called from TRACE_IRQS_ON/OFF_DEBUG
macros which run in int3 ist entry, probing it may cause a soft
lockup.

This happens when the kernel built with CONFIG_DYNAMIC_FTRACE=y
and CONFIG_TRACE_IRQFLAGS=y.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Reviewed-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Jan Beulich <JBeulich@suse.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Seiji Aguchi <seiji.aguchi@hds.com>
Link: http://lkml.kernel.org/r/20140417081712.26341.32994.stgit@ltc230.yrl.intra.hitachi.co.jp
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-04-24 10:02:57 +02:00
Masami Hiramatsu
376e242429 kprobes: Introduce NOKPROBE_SYMBOL() macro to maintain kprobes blacklist
Introduce NOKPROBE_SYMBOL() macro which builds a kprobes
blacklist at kernel build time.

The usage of this macro is similar to EXPORT_SYMBOL(),
placed after the function definition:

  NOKPROBE_SYMBOL(function);

Since this macro will inhibit inlining of static/inline
functions, this patch also introduces a nokprobe_inline macro
for static/inline functions. In this case, we must use
NOKPROBE_SYMBOL() for the inline function caller.

When CONFIG_KPROBES=y, the macro stores the given function
address in the "_kprobe_blacklist" section.

Since the data structures are not fully initialized by the
macro (because there is no "size" information),  those
are re-initialized at boot time by using kallsyms.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Link: http://lkml.kernel.org/r/20140417081705.26341.96719.stgit@ltc230.yrl.intra.hitachi.co.jp
Cc: Alok Kataria <akataria@vmware.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Christopher Li <sparse@chrisli.org>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: Jan-Simon Möller <dl9pf@gmx.de>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: linux-arch@vger.kernel.org
Cc: linux-doc@vger.kernel.org
Cc: linux-sparse@vger.kernel.org
Cc: virtualization@lists.linux-foundation.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-04-24 10:02:56 +02:00
Masami Hiramatsu
be8f274323 kprobes: Prohibit probing on .entry.text code
.entry.text is a code area which is used for interrupt/syscall
entries, which includes many sensitive code.
Thus, it is better to prohibit probing on all of such code
instead of a part of that.
Since some symbols are already registered on kprobe blacklist,
this also removes them from the blacklist.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Reviewed-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David S. Miller <davem@davemloft.net>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Jonathan Lebon <jlebon@redhat.com>
Cc: Seiji Aguchi <seiji.aguchi@hds.com>
Link: http://lkml.kernel.org/r/20140417081658.26341.57354.stgit@ltc230.yrl.intra.hitachi.co.jp
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-04-24 10:02:56 +02:00
Masami Hiramatsu
6a5022a56a kprobes/x86: Allow to handle reentered kprobe on single-stepping
Since the NMI handlers(e.g. perf) can interrupt in the
single stepping (or preparing the single stepping, do_debug
etc.), we should consider a kprobe is hit in the NMI
handler. Even in that case, the kprobe is allowed to be
reentered as same as the kprobes hit in kprobe handlers
(KPROBE_HIT_ACTIVE or KPROBE_HIT_SSDONE).

The real issue will happen when a kprobe hit while another
reentered kprobe is processing (KPROBE_REENTER), because
we already consumed a saved-area for the previous kprobe.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Reviewed-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Jonathan Lebon <jlebon@redhat.com>
Link: http://lkml.kernel.org/r/20140417081651.26341.10593.stgit@ltc230.yrl.intra.hitachi.co.jp
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-04-24 10:02:55 +02:00