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2022-10-22Merge branch 'x86/urgent' into x86/core, to resolve conflictIngo Molnar1-8/+11
There's a conflict between the call-depth tracking commits in x86/core: ee3e2469b346 ("x86/ftrace: Make it call depth tracking aware") 36b64f101219 ("x86/ftrace: Rebalance RSB") eac828eaef29 ("x86/ftrace: Remove ftrace_epilogue()") And these fixes in x86/urgent: 883bbbffa5a4 ("ftrace,kcfi: Separate ftrace_stub() and ftrace_stub_graph()") b5f1fc318440 ("x86/ftrace: Remove ftrace_epilogue()") It's non-trivial overlapping modifications - resolve them. Conflicts: arch/x86/kernel/ftrace_64.S Signed-off-by: Ingo Molnar <mingo@kernel.org>
2022-10-20ftrace,kcfi: Separate ftrace_stub() and ftrace_stub_graph()Peter Zijlstra1-8/+9
Different function signatures means they needs to be different functions; otherwise CFI gets upset. As triggered by the ftrace boot tests: [] CFI failure at ftrace_return_to_handler+0xac/0x16c (target: ftrace_stub+0x0/0x14; expected type: 0x0a5d5347) Fixes: 3c516f89e17e ("x86: Add support for CONFIG_CFI_CLANG") Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Mark Rutland <mark.rutland@arm.com> Tested-by: Mark Rutland <mark.rutland@arm.com> Link: https://lkml.kernel.org/r/Y06dg4e1xF6JTdQq@hirez.programming.kicks-ass.net
2022-10-20x86/ftrace: Remove ftrace_epilogue()Peter Zijlstra1-15/+6
Remove the weird jumps to RET and simply use RET. This then promotes ftrace_stub() to a real function; which becomes important for kcfi. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20220915111148.719080593@infradead.org Signed-off-by: Peter Zijlstra <peterz@infradead.org>
2022-10-17x86/ftrace: Make it call depth tracking awarePeter Zijlstra1-2/+20
Since ftrace has trampolines, don't use thunks for the __fentry__ site but instead require that every function called from there includes accounting. This very much includes all the direct-call functions. Additionally, ftrace uses ROP tricks in two places: - return_to_handler(), and - ftrace_regs_caller() when pt_regs->orig_ax is set by a direct-call. return_to_handler() already uses a retpoline to replace an indirect-jump to defeat IBT, since this is a jump-type retpoline, make sure there is no accounting done and ALTERNATIVE the RET into a ret. ftrace_regs_caller() does much the same and gets the same treatment. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20220915111148.927545073@infradead.org
2022-10-17x86/ftrace: Rebalance RSBPeter Zijlstra1-0/+11
ftrace_regs_caller() uses a PUSH;RET pattern to tail-call into a direct-call function, this unbalances the RSB, fix that. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20220915111148.823216933@infradead.org
2022-10-17x86/ftrace: Remove ftrace_epilogue()Peter Zijlstra1-15/+6
Remove the weird jumps to RET and simply use RET. This then promotes ftrace_stub() to a real function; which becomes important for kcfi. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20220915111148.719080593@infradead.org
2022-06-06x86/ftrace: Remove OBJECT_FILES_NON_STANDARD usageJosh Poimboeuf1-3/+8
The file-wide OBJECT_FILES_NON_STANDARD annotation is used with CONFIG_FRAME_POINTER to tell objtool to skip the entire file when frame pointers are enabled. However that annotation is now deprecated because it doesn't work with IBT, where objtool runs on vmlinux.o instead of individual translation units. Instead, use more fine-grained function-specific annotations: - The 'save_mcount_regs' macro does funny things with the frame pointer. Use STACK_FRAME_NON_STANDARD_FP to tell objtool to ignore the functions using it. - The return_to_handler() "function" isn't actually a callable function. Instead of being called, it's returned to. The real return address isn't on the stack, so unwinding is already doomed no matter which unwinder is used. So just remove the STT_FUNC annotation, telling objtool to ignore it. That also removes the implicit ANNOTATE_NOENDBR, which now needs to be made explicit. Fixes the following warning: vmlinux.o: warning: objtool: __fentry__+0x16: return with modified stack frame Fixes: ed53a0d97192 ("x86/alternative: Use .ibt_endbr_seal to seal indirect calls") Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org> Link: https://lore.kernel.org/r/b7a7a42fe306aca37826043dac89e113a1acdbac.1654268610.git.jpoimboe@kernel.org
2022-03-15x86/ibt,ftrace: Annotate ftrace code patchingPeter Zijlstra1-0/+7
These are code patching sites, not indirect targets. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Josh Poimboeuf <jpoimboe@redhat.com> Link: https://lore.kernel.org/r/20220308154318.936599479@infradead.org
2022-03-15x86/ibt,ftrace: Make function-graph play nicePeter Zijlstra1-4/+17
Return trampoline must not use indirect branch to return; while this preserves the RSB, it is fundamentally incompatible with IBT. Instead use a retpoline like ROP gadget that defeats IBT while not unbalancing the RSB. And since ftrace_stub is no longer a plain RET, don't use it to copy from. Since RET is a trivial instruction, poke it directly. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Josh Poimboeuf <jpoimboe@redhat.com> Link: https://lore.kernel.org/r/20220308154318.347296408@infradead.org
2021-12-08x86: Prepare asm files for straight-line-speculationPeter Zijlstra1-4/+4
Replace all ret/retq instructions with RET in preparation of making RET a macro. Since AS is case insensitive it's a big no-op without RET defined. find arch/x86/ -name \*.S | while read file do sed -i 's/\<ret[q]*\>/RET/' $file done Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lore.kernel.org/r/20211204134907.905503893@infradead.org
2021-10-20x86/ftrace: Make function graph use ftrace directlySteven Rostedt (VMware)1-28/+1
We don't need special hook for graph tracer entry point, but instead we can use graph_ops::func function to install the return_hooker. This moves the graph tracing setup _before_ the direct trampoline prepares the stack, so the return_hooker will be called when the direct trampoline is finished. This simplifies the code, because we don't need to take into account the direct trampoline setup when preparing the graph tracer hooker and we can allow function graph tracer on entries registered with direct trampoline. Link: https://lkml.kernel.org/r/20211008091336.33616-4-jolsa@kernel.org [fixed compile error reported by kernel test robot <lkp@intel.com>] Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-10-19x86/ftrace: Remove extra orig rax moveJiri Olsa1-1/+0
There's identical move 2 lines earlier. Link: https://lkml.kernel.org/r/20211008091336.33616-2-jolsa@kernel.org Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-01-26x86/ftrace: Support objtool vmlinux.o validation in ftrace_64.SJosh Poimboeuf1-3/+2
With objtool vmlinux.o validation of return_to_handler(), now that objtool has visibility inside the retpoline, jumping from EMPTY state to a proper function state results in a stack state mismatch. return_to_handler() is actually quite normal despite the underlying magic. Just annotate it as a normal function. Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Link: https://lore.kernel.org/r/14f48e623f61dbdcd84cf27a56ed8ccae73199ef.1611263462.git.jpoimboe@redhat.com
2021-01-26objtool: Combine UNWIND_HINT_RET_OFFSET and UNWIND_HINT_FUNCJosh Poimboeuf1-1/+1
The ORC metadata generated for UNWIND_HINT_FUNC isn't actually very func-like. With certain usages it can cause stack state mismatches because it doesn't set the return address (CFI_RA). Also, users of UNWIND_HINT_RET_OFFSET no longer need to set a custom return stack offset. Instead they just need to specify a func-like situation, so the current ret_offset code is hacky for no good reason. Solve both problems by simplifying the RET_OFFSET handling and converting it into a more useful UNWIND_HINT_FUNC. If we end up needing the old 'ret_offset' functionality again in the future, we should be able to support it pretty easily with the addition of a custom 'sp_offset' in UNWIND_HINT_FUNC. Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Link: https://lore.kernel.org/r/db9d1f5d79dddfbb3725ef6d8ec3477ad199948d.1611263462.git.jpoimboe@redhat.com
2021-01-26x86/ftrace: Add UNWIND_HINT_FUNC annotation for ftrace_stubJosh Poimboeuf1-0/+1
Prevent an unreachable objtool warning after the sibling call detection gets improved. ftrace_stub() is basically a function, annotate it as such. Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Link: https://lore.kernel.org/r/6845e1b2fb0723a95740c6674e548ba38c5ea489.1611263461.git.jpoimboe@redhat.com
2020-11-13livepatch: Use the default ftrace_ops instead of REGS when ARGS is availableSteven Rostedt (VMware)1-0/+4
When CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS is available, the ftrace call will be able to set the ip of the calling function. This will improve the performance of live kernel patching where it does not need all the regs to be stored just to change the instruction pointer. If all archs that support live kernel patching also support HAVE_DYNAMIC_FTRACE_WITH_ARGS, then the architecture specific function klp_arch_set_pc() could be made generic. It is possible that an arch can support HAVE_DYNAMIC_FTRACE_WITH_ARGS but not HAVE_DYNAMIC_FTRACE_WITH_REGS and then have access to live patching. Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Jiri Kosina <jikos@kernel.org> Cc: live-patching@vger.kernel.org Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Miroslav Benes <mbenes@suse.cz> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-11-13ftrace/x86: Allow for arguments to be passed in to ftrace_regs by defaultSteven Rostedt (VMware)1-2/+9
Currently, the only way to get access to the registers of a function via a ftrace callback is to set the "FL_SAVE_REGS" bit in the ftrace_ops. But as this saves all regs as if a breakpoint were to trigger (for use with kprobes), it is expensive. The regs are already saved on the stack for the default ftrace callbacks, as that is required otherwise a function being traced will get the wrong arguments and possibly crash. And on x86, the arguments are already stored where they would be on a pt_regs structure to use that code for both the regs version of a callback, it makes sense to pass that information always to all functions. If an architecture does this (as x86_64 now does), it is to set HAVE_DYNAMIC_FTRACE_WITH_ARGS, and this will let the generic code that it could have access to arguments without having to set the flags. This also includes having the stack pointer being saved, which could be used for accessing arguments on the stack, as well as having the function graph tracer not require its own trampoline! Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-06-29x86/ftrace: Do not jump to direct code in created trampolinesSteven Rostedt (VMware)1-0/+1
When creating a trampoline based on the ftrace_regs_caller code, nop out the jnz test that would jmup to the code that would return to a direct caller (stored in the ORIG_RAX field) and not back to the function that called it. Link: http://lkml.kernel.org/r/20200422162750.638839749@goodmis.org Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-06-29x86/ftrace: Only have the builtin ftrace_regs_caller call direct hooksSteven Rostedt (VMware)1-2/+1
If a direct hook is attached to a function that ftrace also has a function attached to it, then it is required that the ftrace_ops_list_func() is used to iterate over the registered ftrace callbacks. This will also include the direct ftrace_ops helper, that tells ftrace_regs_caller where to return to (the direct callback and not the function that called it). As this direct helper is only to handle the case of ftrace callbacks attached to the same function as the direct callback, the ftrace callback allocated trampolines (used to only call them), should never be used to return back to a direct callback. Only copy the portion of the ftrace_regs_caller that will return back to what called it, and not the portion that returns back to the direct caller. The direct ftrace_ops must then pick the ftrace_regs_caller builtin function as its own trampoline to ensure that it will never have one allocated for it (which would not include the handling of direct callbacks). Link: http://lkml.kernel.org/r/20200422162750.495903799@goodmis.org Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-06-29x86/ftrace: Make non direct case the default in ftrace_regs_callerSteven Rostedt (VMware)1-16/+15
If a direct function is hooked along with one of the ftrace registered functions, then the ftrace_regs_caller is attached to the function that shares the direct hook as well as the ftrace hook. The ftrace_regs_caller will call ftrace_ops_list_func() that iterates through all the registered ftrace callbacks, and if there's a direct callback attached to that function, the direct ftrace_ops callback is called to notify that ftrace_regs_caller to return to the direct caller instead of going back to the function that called it. But this is a very uncommon case. Currently, the code has it as the default case. Modify ftrace_regs_caller to make the default case (the non jump) to just return normally, and have the jump to the handling of the direct caller. Link: http://lkml.kernel.org/r/20200422162750.350373278@goodmis.org Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-06-11x86/entry/64: Move non entry code into .text sectionThomas Gleixner1-1/+1
All ASM code which is not part of the entry functionality can move out into the .text section. No reason to keep it in the non-instrumentable entry section. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com> Acked-by: Peter Zijlstra <peterz@infradead.org> Link: https://lkml.kernel.org/r/20200505134340.227579223@linutronix.de
2020-04-30x86: Change {JMP,CALL}_NOSPEC argumentPeter Zijlstra1-2/+2
In order to change the {JMP,CALL}_NOSPEC macros to call out-of-line versions of the retpoline magic, we need to remove the '%' from the argument, such that we can paste it onto symbol names. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Josh Poimboeuf <jpoimboe@redhat.com> Link: https://lkml.kernel.org/r/20200428191700.151623523@infradead.org
2020-04-22x86,ftrace: Shrink ftrace_regs_caller() by one bytePeter Zijlstra1-2/+2
'Optimize' ftrace_regs_caller. Instead of comparing against an immediate, the more natural way to test for zero on x86 is: 'test %r,%r'. 48 83 f8 00 cmp $0x0,%rax 74 49 je 226 <ftrace_regs_call+0xa3> 48 85 c0 test %rax,%rax 74 49 je 225 <ftrace_regs_call+0xa2> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Miroslav Benes <mbenes@suse.cz> Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com> Acked-by: Josh Poimboeuf <jpoimboe@redhat.com> Link: https://lkml.kernel.org/r/20200416115118.867411350@infradead.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-04-22x86,ftrace: Use SIZEOF_PTREGSPeter Zijlstra1-2/+2
There's a convenient macro for 'SS+8' called FRAME_SIZE. Use it to clarify things. (entry/calling.h calls this SIZEOF_PTREGS but we're using asm/ptrace-abi.h) Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Miroslav Benes <mbenes@suse.cz> Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com> Acked-by: Josh Poimboeuf <jpoimboe@redhat.com> Link: https://lkml.kernel.org/r/20200416115118.808485515@infradead.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-04-22x86,ftrace: Fix ftrace_regs_caller() unwindPeter Zijlstra1-17/+15
The ftrace_regs_caller() trampoline does something 'funny' when there is a direct-caller present. In that case it stuffs the 'direct-caller' address on the return stack and then exits the function. This then results in 'returning' to the direct-caller with the exact registers we came in with -- an indirect tail-call without using a register. This however (rightfully) confuses objtool because the function shares a few instruction in order to have a single exit path, but the stack layout is different for them, depending through which path we came there. This is currently cludged by forcing the stack state to the non-direct case, but this generates actively wrong (ORC) unwind information for the direct case, leading to potential broken unwinds. Fix this issue by fully separating the exit paths. This results in having to poke a second RET into the trampoline copy, see ftrace_regs_caller_ret. This brings us to a second objtool problem, in order for it to perceive the 'jmp ftrace_epilogue' as a function exit, it needs to be recognised as a tail call. In order to make that happen, ftrace_epilogue needs to be the start of an STT_FUNC, so re-arrange code to make this so. Finally, a third issue is that objtool requires functions to exit with the same stack layout they started with, which is obviously violated in the direct case, employ the new HINT_RET_OFFSET to tell objtool this is an expected exception. Together, this results in generating correct ORC unwind information for the ftrace_regs_caller() function and it's trampoline copies. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Miroslav Benes <mbenes@suse.cz> Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com> Acked-by: Josh Poimboeuf <jpoimboe@redhat.com> Link: https://lkml.kernel.org/r/20200416115118.749606694@infradead.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-11-27Merge tag 'trace-v5.5' of ↵Linus Torvalds1-6/+36
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing updates from Steven Rostedt: "New tracing features: - New PERMANENT flag to ftrace_ops when attaching a callback to a function. As /proc/sys/kernel/ftrace_enabled when set to zero will disable all attached callbacks in ftrace, this has a detrimental impact on live kernel tracing, as it disables all that it patched. If a ftrace_ops is registered to ftrace with the PERMANENT flag set, it will prevent ftrace_enabled from being disabled, and if ftrace_enabled is already disabled, it will prevent a ftrace_ops with PREMANENT flag set from being registered. - New register_ftrace_direct(). As eBPF would like to register its own trampolines to be called by the ftrace nop locations directly, without going through the ftrace trampoline, this function has been added. This allows for eBPF trampolines to live along side of ftrace, perf, kprobe and live patching. It also utilizes the ftrace enabled_functions file that keeps track of functions that have been modified in the kernel, to allow for security auditing. - Allow for kernel internal use of ftrace instances. Subsystems in the kernel can now create and destroy their own tracing instances which allows them to have their own tracing buffer, and be able to record events without worrying about other users from writing over their data. - New seq_buf_hex_dump() that lets users use the hex_dump() in their seq_buf usage. - Notifications now added to tracing_max_latency to allow user space to know when a new max latency is hit by one of the latency tracers. - Wider spread use of generic compare operations for use of bsearch and friends. - More synthetic event fields may be defined (32 up from 16) - Use of xarray for architectures with sparse system calls, for the system call trace events. This along with small clean ups and fixes" * tag 'trace-v5.5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (51 commits) tracing: Enable syscall optimization for MIPS tracing: Use xarray for syscall trace events tracing: Sample module to demonstrate kernel access to Ftrace instances. tracing: Adding new functions for kernel access to Ftrace instances tracing: Fix Kconfig indentation ring-buffer: Fix typos in function ring_buffer_producer ftrace: Use BIT() macro ftrace: Return ENOTSUPP when DYNAMIC_FTRACE_WITH_DIRECT_CALLS is not configured ftrace: Rename ftrace_graph_stub to ftrace_stub_graph ftrace: Add a helper function to modify_ftrace_direct() to allow arch optimization ftrace: Add helper find_direct_entry() to consolidate code ftrace: Add another check for match in register_ftrace_direct() ftrace: Fix accounting bug with direct->count in register_ftrace_direct() ftrace/selftests: Fix spelling mistake "wakeing" -> "waking" tracing: Increase SYNTH_FIELDS_MAX for synthetic_events ftrace/samples: Add a sample module that implements modify_ftrace_direct() ftrace: Add modify_ftrace_direct() tracing: Add missing "inline" in stub function of latency_fsnotify() tracing: Remove stray tab in TRACE_EVAL_MAP_FILE's help text tracing: Use seq_buf_hex_dump() to dump buffers ...
2019-11-13ftrace/x86: Tell objtool to ignore nondeterministic ftrace stack layoutJosh Poimboeuf1-1/+11
Objtool complains about the new ftrace direct trampoline code: arch/x86/kernel/ftrace_64.o: warning: objtool: ftrace_regs_caller()+0x190: stack state mismatch: cfa1=7+16 cfa2=7+24 Typically, code has a deterministic stack layout, such that at a given instruction address, the stack frame size is always the same. That's not the case for the new ftrace_regs_caller() code after it adjusts the stack for the direct case. Just plead ignorance and assume it's always the non-direct path. Note this creates a tiny window for ORC to get confused. Link: http://lkml.kernel.org/r/20191108225100.ea3bhsbdf6oerj6g@treble Reported-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-13ftrace/x86: Add register_ftrace_direct() for custom trampolinesSteven Rostedt (VMware)1-7/+27
Enable x86 to allow for register_ftrace_direct(), where a custom trampoline may be called directly from an ftrace mcount/fentry location. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-10-25x86/ftrace: Get rid of function_hookBorislav Petkov1-7/+6
History lesson courtesy of Steve: "When ftrace first was introduced to the kernel, it used gcc's mcount profiling mechanism. The mcount mechanism would add a call to "mcount" at the start of every function but after the stack frame was set up. Later, in gcc 4.6, gcc introduced -mfentry, that would create a call to "__fentry__" instead of "mcount", before the stack frame was set up. In order to handle both cases, ftrace defined a macro "function_hook" that would be either "mcount" or "__fentry__" depending on which one was being used. The Linux kernel no longer supports the "mcount" method, thus there's no reason to keep the "function_hook" define around. Simply use "__fentry__", as there is no ambiguity to the name anymore." Drop it everywhere. Signed-off-by: Borislav Petkov <bp@suse.de> Acked-by: Jiri Slaby <jslaby@suse.cz> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: linux-doc@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: Peter Zijlstra <peterz@infradead.org> Cc: "Steven Rostedt (VMware)" <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: x86@kernel.org Link: http://lkml.kernel.org/r/20191018124800.0a7006bb@gandalf.local.home
2019-10-18x86/asm: Replace WEAK uses by SYM_INNER_LABEL_ALIGNJiri Slaby1-1/+1
Use the new SYM_INNER_LABEL_ALIGN for WEAK entries in the middle of x86 assembly functions. And make sure WEAK is not defined for x86 anymore as these were the last users. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: linux-arch@vger.kernel.org Cc: Mark Rutland <mark.rutland@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com> Cc: "Steven Rostedt (VMware)" <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: x86-ml <x86@kernel.org> Link: https://lkml.kernel.org/r/20191011115108.12392-29-jslaby@suse.cz
2019-10-18x86/asm: Change all ENTRY+ENDPROC to SYM_FUNC_*Jiri Slaby1-10/+10
These are all functions which are invoked from elsewhere, so annotate them as global using the new SYM_FUNC_START and their ENDPROC's by SYM_FUNC_END. Make sure ENTRY/ENDPROC is not defined on X86_64, given these were the last users. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> [hibernate] Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> [xen bits] Acked-by: Herbert Xu <herbert@gondor.apana.org.au> [crypto] Cc: Allison Randal <allison@lohutok.net> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Andy Shevchenko <andy@infradead.org> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Armijn Hemel <armijn@tjaldur.nl> Cc: Cao jin <caoj.fnst@cn.fujitsu.com> Cc: Darren Hart <dvhart@infradead.org> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Enrico Weigelt <info@metux.net> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jim Mattson <jmattson@google.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Juergen Gross <jgross@suse.com> Cc: Kate Stewart <kstewart@linuxfoundation.org> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: kvm ML <kvm@vger.kernel.org> Cc: Len Brown <len.brown@intel.com> Cc: linux-arch@vger.kernel.org Cc: linux-crypto@vger.kernel.org Cc: linux-efi <linux-efi@vger.kernel.org> Cc: linux-efi@vger.kernel.org Cc: linux-pm@vger.kernel.org Cc: Mark Rutland <mark.rutland@arm.com> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Pavel Machek <pavel@ucw.cz> Cc: Peter Zijlstra <peterz@infradead.org> Cc: platform-driver-x86@vger.kernel.org Cc: "Radim Krčmář" <rkrcmar@redhat.com> Cc: Sean Christopherson <sean.j.christopherson@intel.com> Cc: Stefano Stabellini <sstabellini@kernel.org> Cc: "Steven Rostedt (VMware)" <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vitaly Kuznetsov <vkuznets@redhat.com> Cc: Wanpeng Li <wanpengli@tencent.com> Cc: Wei Huang <wei@redhat.com> Cc: x86-ml <x86@kernel.org> Cc: xen-devel@lists.xenproject.org Cc: Xiaoyao Li <xiaoyao.li@linux.intel.com> Link: https://lkml.kernel.org/r/20191011115108.12392-25-jslaby@suse.cz
2019-10-18x86/asm/64: Change all ENTRY+END to SYM_CODE_*Jiri Slaby1-2/+2
Change all assembly code which is marked using END (and not ENDPROC). Switch all these to the appropriate new annotation SYM_CODE_START and SYM_CODE_END. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> [xen bits] Cc: Andy Lutomirski <luto@kernel.org> Cc: Cao jin <caoj.fnst@cn.fujitsu.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Juergen Gross <jgross@suse.com> Cc: linux-arch@vger.kernel.org Cc: Maran Wilson <maran.wilson@oracle.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stefano Stabellini <sstabellini@kernel.org> Cc: "Steven Rostedt (VMware)" <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: x86-ml <x86@kernel.org> Cc: xen-devel@lists.xenproject.org Link: https://lkml.kernel.org/r/20191011115108.12392-24-jslaby@suse.cz
2019-10-18x86/asm: Use SYM_INNER_LABEL instead of GLOBALJiri Slaby1-8/+8
The GLOBAL macro had several meanings and is going away. Convert all the inner function labels marked with GLOBAL to use SYM_INNER_LABEL instead. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Andy Lutomirski <luto@kernel.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: linux-arch@vger.kernel.org Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: "Steven Rostedt (VMware)" <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: x86-ml <x86@kernel.org> Link: https://lkml.kernel.org/r/20191011115108.12392-18-jslaby@suse.cz
2019-06-25x86/stackframe, x86/ftrace: Add pt_regs frame annotationsPeter Zijlstra1-0/+3
When CONFIG_FRAME_POINTER, we should mark pt_regs frames. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-05-10ftrace/x86: Remove mcount supportSteven Rostedt (VMware)1-27/+1
There's two methods of enabling function tracing in Linux on x86. One is with just "gcc -pg" and the other is "gcc -pg -mfentry". The former will use calls to a special function "mcount" after the frame is set up in all C functions. The latter will add calls to a special function called "fentry" as the very first instruction of all C functions. At compile time, there is a check to see if gcc supports, -mfentry, and if it does, it will use that, because it is more versatile and less error prone for function tracing. Starting with v4.19, the minimum gcc supported to build the Linux kernel, was raised to version 4.6. That also happens to be the first gcc version to support -mfentry. Since on x86, using gcc versions from 4.6 and beyond will unconditionally enable the -mfentry, it will no longer use mcount as the method for inserting calls into the C functions of the kernel. This means that there is no point in continuing to maintain mcount in x86. Remove support for using mcount. This makes the code less complex, and will also allow it to be simplified in the future. Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Jiri Kosina <jkosina@suse.cz> Acked-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-12-19x86/ftrace: Do not call function graph from dynamic trampolinesSteven Rostedt (VMware)1-4/+4
Since commit 79922b8009c07 ("ftrace: Optimize function graph to be called directly"), dynamic trampolines should not be calling the function graph tracer at the end. If they do, it could cause the function graph tracer to trace functions that it filtered out. Right now it does not cause a problem because there's a test to check if the function graph tracer is attached to the same function as the function tracer, which for now is true. But the function graph tracer is undergoing changes that can make this no longer true which will cause the function graph tracer to trace other functions. For example: # cd /sys/kernel/tracing/ # echo do_IRQ > set_ftrace_filter # mkdir instances/foo # echo ip_rcv > instances/foo/set_ftrace_filter # echo function_graph > current_tracer # echo function > instances/foo/current_tracer Would cause the function graph tracer to trace both do_IRQ and ip_rcv, if the current tests change. As the current tests prevent this from being a problem, this code does not need to be backported. But it does make the code cleaner. Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Borislav Petkov <bp@alien8.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: x86@kernel.org Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-01-28Merge branch 'x86-urgent-for-linus' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Thomas Gleixner: "A set of small fixes for 4.15: - Fix vmapped stack synchronization on systems with 4-level paging and a large amount of memory caused by a missing 5-level folding which made the pgd synchronization logic to fail and causing double faults. - Add a missing sanity check in the vmalloc_fault() logic on 5-level paging systems. - Bring back protection against accessing a freed initrd in the microcode loader which was lost by a wrong merge conflict resolution. - Extend the Broadwell micro code loading sanity check. - Add a missing ENDPROC annotation in ftrace assembly code which makes ORC unhappy. - Prevent loading the AMD power module on !AMD platforms. The load itself is uncritical, but an unload attempt results in a kernel crash. - Update Peter Anvins role in the MAINTAINERS file" * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/ftrace: Add one more ENDPROC annotation x86: Mark hpa as a "Designated Reviewer" for the time being x86/mm/64: Tighten up vmalloc_fault() sanity checks on 5-level kernels x86/mm/64: Fix vmapped stack syncing on very-large-memory 4-level systems x86/microcode: Fix again accessing initrd after having been freed x86/microcode/intel: Extend BDW late-loading further with LLC size check perf/x86/amd/power: Do not load AMD power module on !AMD platforms
2018-01-28x86/ftrace: Add one more ENDPROC annotationJosh Poimboeuf1-1/+1
When ORC support was added for the ftrace_64.S code, an ENDPROC for function_hook() was missed. This results in the following warning: arch/x86/kernel/ftrace_64.o: warning: objtool: .entry.text+0x0: unreachable instruction Fixes: e2ac83d74a4d ("x86/ftrace: Fix ORC unwinding from ftrace handlers") Reported-by: Steven Rostedt <rostedt@goodmis.org> Reported-by: Borislav Petkov <bp@alien8.de> Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Ingo Molnar <mingo@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: https://lkml.kernel.org/r/20180128022150.dqierscqmt3uwwsr@treble
2018-01-23x86/ftrace: Fix ORC unwinding from ftrace handlersJosh Poimboeuf1-9/+15
Steven Rostedt discovered that the ftrace stack tracer is broken when it's used with the ORC unwinder. The problem is that objtool is instructed by the Makefile to ignore the ftrace_64.S code, so it doesn't generate any ORC data for it. Fix it by making the asm code objtool-friendly: - Objtool doesn't like the fact that save_mcount_regs pushes RBP at the beginning, but it's never restored (directly, at least). So just skip the original RBP push, which is only needed for frame pointers anyway. - Annotate some functions as normal callable functions with ENTRY/ENDPROC. - Add an empty unwind hint to return_to_handler(). The return address isn't on the stack, so there's nothing ORC can do there. It will just punt in the unlikely case it tries to unwind from that code. With all that fixed, remove the OBJECT_FILES_NON_STANDARD Makefile annotation so objtool can read the file. Link: http://lkml.kernel.org/r/20180123040746.ih4ep3tk4pbjvg7c@treble Reported-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-01-12x86/retpoline/ftrace: Convert ftrace assembler indirect jumpsDavid Woodhouse1-4/+4
Convert all indirect jumps in ftrace assembler code to use non-speculative sequences when CONFIG_RETPOLINE is enabled. Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Arjan van de Ven <arjan@linux.intel.com> Acked-by: Ingo Molnar <mingo@kernel.org> Cc: gnomes@lxorguk.ukuu.org.uk Cc: Rik van Riel <riel@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: thomas.lendacky@amd.com Cc: Peter Zijlstra <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Jiri Kosina <jikos@kernel.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Kees Cook <keescook@google.com> Cc: Tim Chen <tim.c.chen@linux.intel.com> Cc: Greg Kroah-Hartman <gregkh@linux-foundation.org> Cc: Paul Turner <pjt@google.com> Link: https://lkml.kernel.org/r/1515707194-20531-8-git-send-email-dwmw@amazon.co.uk
2017-11-02License cleanup: add SPDX GPL-2.0 license identifier to files with no licenseGreg Kroah-Hartman1-0/+1
Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-03-24x86/ftrace: Use Makefile logic instead of #ifdef for compiling ftrace_*.oSteven Rostedt (VMware)1-4/+0
Currently ftrace_32.S and ftrace_64.S are compiled even when CONFIG_FUNCTION_TRACER is not set. This means there's an unnecessary #ifdef to protect the code. Instead of using preprocessor directives, only compile those files when FUNCTION_TRACER is defined. Suggested-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com> Reviewed-by: Ingo Molnar <mingo@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/20170316210043.peycxdxktwwn6cid@treble Link: http://lkml.kernel.org/r/20170323143446.217684991@goodmis.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-03-24x86/ftrace: Rename mcount_64.S to ftrace_64.SSteven Rostedt (VMware)1-0/+336
With the advent of -mfentry that uses the new "fentry" hook over mcount, the mcount name is obsolete. Having the code file that ftrace hooks into called "mcount*.S" is rather misleading. Rename it to ftrace_64.S and remove the file name reference. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Reviewed-by: Ingo Molnar <mingo@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/20170323143445.490601451@goodmis.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>