Lines Matching refs:a

8 The kernel CONFIG_STACK_VALIDATION option enables a host tool named
9 objtool which runs at compile time.  It has a "check" subcommand which
11 It enforces a set of rules on asm code and C inline assembly code so
19 alternative execution paths to a given instruction (or set of
33 a) More reliable stack traces for frame pointer enabled kernels
52    functions which call other functions must first create a stack frame
53    and update the frame pointer.  If a first function doesn't properly
54    create a stack frame before calling a second function, the *caller*
90    skipped on a stack trace.
93        beginning of a function before the stack frame has been created,
123    ENTRY/ENDPROC macros.  If objtool finds a return instruction
124    outside of a function, it flags an error since that usually indicates
143    designed.  If function A doesn't create a stack frame before calling
149    a) the jump is part of a switch statement; or
154    This rule is needed so that objtool can reliably analyze all of a
155    function's code paths.  If a function jumps to code in another file,
156    and it's not a sibling call, objtool has no way to follow the jump
157    because it only analyzes a single file at a time.
163    This rule is just a sanity check to ensure that callable functions
185    The func() function made a function call without first saving and/or
188    If the error is for an asm file, and func() is indeed a callable
190    FRAME_END macros.  Otherwise, if it's not a callable function, remove
194    If it's a GCC-compiled .c file, the error may be because the function
195    uses an inline asm() statement which has a "call" instruction.  An
196    asm() statement with a call instruction must declare the use of the
207    Objtool couldn't find a code path to reach the instruction.
210    reachable from) a callable function, the function should be annotated
217    a just a bad person, you can tell objtool to ignore it.  See the
220    If it's not actually in a callable function (e.g. kernel entry code),
228    Does the file have data in a text section?  If so, that can confuse
229    objtool's instruction decoder.  Move the data to a more appropriate
235    This is a kernel entry/exit instruction like sysenter or iret.  Such
236    instructions aren't allowed in a callable function, and are most
244    This is a dynamic jump or a jump to an undefined symbol.  Objtool
245    assumed it's a sibling call and detected that the frame pointer
248    If it's not really a sibling call, you may need to move the
251    If the instruction is not actually in a callable function (e.g.
275    This means that funcA() doesn't end with a return instruction or an
280    1) funcA()'s last instruction is a call to a "noreturn" function like
283       objtool maintainer, or you can submit a patch.
285    2) funcA() uses the unreachable() annotation in a section of code
289       might be corrupt due to a gcc bug.  For more details, see:
293 If the error doesn't seem to make sense, it could be a bug in objtool.
304 - To skip validation of a function, use the STACK_FRAME_NON_STANDARD
307 - To skip validation of a file, add
313 - To skip validation of a directory, add