Commit a6e3e6f1 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 'mm-nonmm-stable-2022-12-17-20-32' of... 

Merge tag 'mm-nonmm-stable-2022-12-17-20-32' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull fault-injection updates from Andrew Morton:
 "Some fault-injection improvements from Wei Yongjun which enable
  stacktrace filtering on x86_64"

* tag 'mm-nonmm-stable-2022-12-17-20-32' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
  fault-injection: make stacktrace filter works as expected
  fault-injection: make some stack filter attrs more readable
  fault-injection: skip stacktrace filtering by default
  fault-injection: allow stacktrace filter for x86-64
parents 1ea9d333 f9eeef59

lib/Kconfig.debug

+0 −1
Original line number Diff line number Diff line
@@ -1983,7 +1983,6 @@ config FAIL_SUNRPC 
config FAULT_INJECTION_STACKTRACE_FILTER

	bool "stacktrace filter for fault-injection capabilities"

	depends on FAULT_INJECTION_DEBUG_FS && STACKTRACE_SUPPORT

	depends on !X86_64

	select STACKTRACE

	depends on FRAME_POINTER || MIPS || PPC || S390 || MICROBLAZE || ARM || ARC || X86

	help

lib/fault-inject.c

+14 −8
Original line number Diff line number Diff line
@@ -71,7 +71,7 @@ static bool fail_stacktrace(struct fault_attr *attr) 
	int n, nr_entries;

	bool found = (attr->require_start == 0 && attr->require_end == ULONG_MAX);



	if (depth == 0)

	if (depth == 0 || (found && !attr->reject_start && !attr->reject_end))

		return found;



	nr_entries = stack_trace_save(entries, depth, 1);
@@ -102,10 +102,16 @@ static inline bool fail_stacktrace(struct fault_attr *attr) 


bool should_fail_ex(struct fault_attr *attr, ssize_t size, int flags)

{

	bool stack_checked = false;



	if (in_task()) {

		unsigned int fail_nth = READ_ONCE(current->fail_nth);



		if (fail_nth) {

			if (!fail_stacktrace(attr))

				return false;



			stack_checked = true;

			fail_nth--;

			WRITE_ONCE(current->fail_nth, fail_nth);

			if (!fail_nth)
@@ -125,6 +131,9 @@ bool should_fail_ex(struct fault_attr *attr, ssize_t size, int flags) 
	if (atomic_read(&attr->times) == 0)

		return false;



	if (!stack_checked && !fail_stacktrace(attr))

		return false;



	if (atomic_read(&attr->space) > size) {

		atomic_sub(size, &attr->space);

		return false;
@@ -139,9 +148,6 @@ bool should_fail_ex(struct fault_attr *attr, ssize_t size, int flags) 
	if (attr->probability <= get_random_u32_below(100))

		return false;



	if (!fail_stacktrace(attr))

		return false;



fail:

	if (!(flags & FAULT_NOWARN))

		fail_dump(attr);
@@ -226,10 +232,10 @@ struct dentry *fault_create_debugfs_attr(const char *name, 
#ifdef CONFIG_FAULT_INJECTION_STACKTRACE_FILTER

	debugfs_create_stacktrace_depth("stacktrace-depth", mode, dir,

					&attr->stacktrace_depth);

	debugfs_create_ul("require-start", mode, dir, &attr->require_start);

	debugfs_create_ul("require-end", mode, dir, &attr->require_end);

	debugfs_create_ul("reject-start", mode, dir, &attr->reject_start);

	debugfs_create_ul("reject-end", mode, dir, &attr->reject_end);

	debugfs_create_xul("require-start", mode, dir, &attr->require_start);

	debugfs_create_xul("require-end", mode, dir, &attr->require_end);

	debugfs_create_xul("reject-start", mode, dir, &attr->reject_start);

	debugfs_create_xul("reject-end", mode, dir, &attr->reject_end);

#endif /* CONFIG_FAULT_INJECTION_STACKTRACE_FILTER */



	attr->dname = dget(dir);