Memory profiling can be shut down due to reasons like a failure during initialization. When this happens, the user should not be able to re-enable it. Current sysctrl interface does not handle this properly and will allow re-enabling memory profiling. Fix this by checking for this condition during sysctrl write operation. Signed-off-by: Suren Baghdasaryan --- lib/alloc_tag.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/lib/alloc_tag.c b/lib/alloc_tag.c index 95688c4cba7a..79891528e7b6 100644 --- a/lib/alloc_tag.c +++ b/lib/alloc_tag.c @@ -767,6 +767,16 @@ struct page_ext_operations page_alloc_tagging_ops = { EXPORT_SYMBOL(page_alloc_tagging_ops); #ifdef CONFIG_SYSCTL +static int proc_mem_profiling_handler(const struct ctl_table *table, int write, + void *buffer, size_t *lenp, loff_t *ppos) +{ + if (!mem_profiling_support && write) + return -EINVAL; + + return proc_do_static_key(table, write, buffer, lenp, ppos); +} + + static struct ctl_table memory_allocation_profiling_sysctls[] = { { .procname = "mem_profiling", @@ -776,7 +786,7 @@ static struct ctl_table memory_allocation_profiling_sysctls[] = { #else .mode = 0644, #endif - .proc_handler = proc_do_static_key, + .proc_handler = proc_mem_profiling_handler, }, }; -- 2.51.0.384.g4c02a37b29-goog