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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2019-05-15 16:05:47 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2019-05-15 16:05:47 -0700 |
| commit | d2d8b146043ae7e250aef1fb312971f6f479d487 (patch) | |
| tree | 22db8758a5aa0bc850ba8f83fe57b1f679924d0a /arch/x86/entry | |
| parent | 2bbacd1a92788ee334c7e92b765ea16ebab68dfe (diff) | |
| parent | 693713cbdb3a4bda5a8a678c31f06560bbb14657 (diff) | |
Merge tag 'trace-v5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing updates from Steven Rostedt:
"The major changes in this tracing update includes:
- Removal of non-DYNAMIC_FTRACE from 32bit x86
- Removal of mcount support from x86
- Emulating a call from int3 on x86_64, fixes live kernel patching
- Consolidated Tracing Error logs file
Minor updates:
- Removal of klp_check_compiler_support()
- kdb ftrace dumping output changes
- Accessing and creating ftrace instances from inside the kernel
- Clean up of #define if macro
- Introduction of TRACE_EVENT_NOP() to disable trace events based on
config options
And other minor fixes and clean ups"
* tag 'trace-v5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (44 commits)
x86: Hide the int3_emulate_call/jmp functions from UML
livepatch: Remove klp_check_compiler_support()
ftrace/x86: Remove mcount support
ftrace/x86_32: Remove support for non DYNAMIC_FTRACE
tracing: Simplify "if" macro code
tracing: Fix documentation about disabling options using trace_options
tracing: Replace kzalloc with kcalloc
tracing: Fix partial reading of trace event's id file
tracing: Allow RCU to run between postponed startup tests
tracing: Fix white space issues in parse_pred() function
tracing: Eliminate const char[] auto variables
ring-buffer: Fix mispelling of Calculate
tracing: probeevent: Fix to make the type of $comm string
tracing: probeevent: Do not accumulate on ret variable
tracing: uprobes: Re-enable $comm support for uprobe events
ftrace/x86_64: Emulate call function while updating in breakpoint handler
x86_64: Allow breakpoints to emulate call instructions
x86_64: Add gap to int3 to allow for call emulation
tracing: kdb: Allow ftdump to skip all but the last few entries
tracing: Add trace_total_entries() / trace_total_entries_cpu()
...
Diffstat (limited to 'arch/x86/entry')
| -rw-r--r-- | arch/x86/entry/entry_64.S | 18 |
1 files changed, 16 insertions, 2 deletions
diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S index 20e45d9b4e15..11aa3b2afa4d 100644 --- a/arch/x86/entry/entry_64.S +++ b/arch/x86/entry/entry_64.S @@ -878,7 +878,7 @@ apicinterrupt IRQ_WORK_VECTOR irq_work_interrupt smp_irq_work_interrupt * @paranoid == 2 is special: the stub will never switch stacks. This is for * #DF: if the thread stack is somehow unusable, we'll still get a useful OOPS. */ -.macro idtentry sym do_sym has_error_code:req paranoid=0 shift_ist=-1 ist_offset=0 +.macro idtentry sym do_sym has_error_code:req paranoid=0 shift_ist=-1 ist_offset=0 create_gap=0 ENTRY(\sym) UNWIND_HINT_IRET_REGS offset=\has_error_code*8 @@ -898,6 +898,20 @@ ENTRY(\sym) jnz .Lfrom_usermode_switch_stack_\@ .endif + .if \create_gap == 1 + /* + * If coming from kernel space, create a 6-word gap to allow the + * int3 handler to emulate a call instruction. + */ + testb $3, CS-ORIG_RAX(%rsp) + jnz .Lfrom_usermode_no_gap_\@ + .rept 6 + pushq 5*8(%rsp) + .endr + UNWIND_HINT_IRET_REGS offset=8 +.Lfrom_usermode_no_gap_\@: + .endif + .if \paranoid call paranoid_entry .else @@ -1129,7 +1143,7 @@ apicinterrupt3 HYPERV_STIMER0_VECTOR \ #endif /* CONFIG_HYPERV */ idtentry debug do_debug has_error_code=0 paranoid=1 shift_ist=IST_INDEX_DB ist_offset=DB_STACK_OFFSET -idtentry int3 do_int3 has_error_code=0 +idtentry int3 do_int3 has_error_code=0 create_gap=1 idtentry stack_segment do_stack_segment has_error_code=1 #ifdef CONFIG_XEN_PV |