mirror of
git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
synced 2026-03-25 08:56:59 +08:00
8715b108cd
Filters should be cleared of init functions during freeing of init
memory when the ftrace dyn records are released. However in current
code, the filters are left as is. This patch clears the hashes of the
saved init functions when the init memory is freed. This fixes the
following issue reproducible with the following sequence of commands for
a test module:
================================================
void bar(void)
{
printk(KERN_INFO "bar!\n");
}
void foo(void)
{
printk(KERN_INFO "foo!\n");
bar();
}
static int __init hello_init(void)
{
printk(KERN_INFO "Hello world!\n");
foo();
return 0;
}
static void __exit hello_cleanup(void)
{
printk(KERN_INFO "Cleaning up module.\n");
}
module_init(hello_init);
module_exit(hello_cleanup);
================================================
Commands:
echo '*:mod:test' > /d/tracing/set_ftrace_filter
echo function > /d/tracing/current_tracer
modprobe test
rmmod test
sleep 1
modprobe test
cat /d/tracing/set_ftrace_filter
Behavior without patch: Init function is still in the filter
Expected behavior: Shouldn't have any of the filters set
Link: http://lkml.kernel.org/r/20171009192931.56401-1-joelaf@google.com
Signed-off-by: Joel Fernandes <joelaf@google.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Linux kernel ============ This file was moved to Documentation/admin-guide/README.rst Please notice that there are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. There are various text files in the Documentation/ subdirectory, several of them using the Restructured Text markup notation. See Documentation/00-INDEX for a list of what is contained in each file. Please read the Documentation/process/changes.rst file, as it contains the requirements for building and running the kernel, and information about the problems which may result by upgrading your kernel.