diff options
| -rw-r--r-- | lib/livepatch/test_klp_callbacks_busy.c | 37 | ||||
| -rwxr-xr-x | tools/testing/selftests/livepatch/test-callbacks.sh | 29 |
2 files changed, 42 insertions, 24 deletions
diff --git a/lib/livepatch/test_klp_callbacks_busy.c b/lib/livepatch/test_klp_callbacks_busy.c index 40beddf8a0e2..7ac845f65be5 100644 --- a/lib/livepatch/test_klp_callbacks_busy.c +++ b/lib/livepatch/test_klp_callbacks_busy.c @@ -5,34 +5,53 @@ #include <linux/module.h> #include <linux/kernel.h> +#include <linux/sched.h> #include <linux/workqueue.h> #include <linux/delay.h> -static int sleep_secs; -module_param(sleep_secs, int, 0644); -MODULE_PARM_DESC(sleep_secs, "sleep_secs (default=0)"); +/* load/run-time control from sysfs writer */ +static bool block_transition; +module_param(block_transition, bool, 0644); +MODULE_PARM_DESC(block_transition, "block_transition (default=false)"); static void busymod_work_func(struct work_struct *work); -static DECLARE_DELAYED_WORK(work, busymod_work_func); +static DECLARE_WORK(work, busymod_work_func); static void busymod_work_func(struct work_struct *work) { - pr_info("%s, sleeping %d seconds ...\n", __func__, sleep_secs); - msleep(sleep_secs * 1000); + pr_info("%s enter\n", __func__); + + while (READ_ONCE(block_transition)) { + /* + * Busy-wait until the sysfs writer has acknowledged a + * blocked transition and clears the flag. + */ + msleep(20); + } + pr_info("%s exit\n", __func__); } static int test_klp_callbacks_busy_init(void) { pr_info("%s\n", __func__); - schedule_delayed_work(&work, - msecs_to_jiffies(1000 * 0)); + schedule_work(&work); + + if (!block_transition) { + /* + * Serialize output: print all messages from the work + * function before returning from init(). + */ + flush_work(&work); + } + return 0; } static void test_klp_callbacks_busy_exit(void) { - cancel_delayed_work_sync(&work); + WRITE_ONCE(block_transition, false); + flush_work(&work); pr_info("%s\n", __func__); } diff --git a/tools/testing/selftests/livepatch/test-callbacks.sh b/tools/testing/selftests/livepatch/test-callbacks.sh index a35289b13c9c..32b57ba07f4f 100755 --- a/tools/testing/selftests/livepatch/test-callbacks.sh +++ b/tools/testing/selftests/livepatch/test-callbacks.sh @@ -356,9 +356,7 @@ livepatch: '$MOD_LIVEPATCH': unpatching complete echo -n "TEST: multiple target modules ... " dmesg -C -load_mod $MOD_TARGET_BUSY sleep_secs=0 -# give $MOD_TARGET_BUSY::busymod_work_func() a chance to run -sleep 5 +load_mod $MOD_TARGET_BUSY block_transition=N load_lp $MOD_LIVEPATCH load_mod $MOD_TARGET unload_mod $MOD_TARGET @@ -366,9 +364,9 @@ disable_lp $MOD_LIVEPATCH unload_lp $MOD_LIVEPATCH unload_mod $MOD_TARGET_BUSY -check_result "% modprobe $MOD_TARGET_BUSY sleep_secs=0 +check_result "% modprobe $MOD_TARGET_BUSY block_transition=N $MOD_TARGET_BUSY: ${MOD_TARGET_BUSY}_init -$MOD_TARGET_BUSY: busymod_work_func, sleeping 0 seconds ... +$MOD_TARGET_BUSY: busymod_work_func enter $MOD_TARGET_BUSY: busymod_work_func exit % modprobe $MOD_LIVEPATCH livepatch: enabling patch '$MOD_LIVEPATCH' @@ -404,11 +402,10 @@ livepatch: '$MOD_LIVEPATCH': unpatching complete $MOD_TARGET_BUSY: ${MOD_TARGET_BUSY}_exit" - # TEST: busy target module # # A similar test as the previous one, but force the "busy" kernel module -# to do longer work. +# to block the livepatch transition. # # The livepatching core will refuse to patch a task that is currently # executing a to-be-patched function -- the consistency model stalls the @@ -417,8 +414,7 @@ $MOD_TARGET_BUSY: ${MOD_TARGET_BUSY}_exit" # function for a long time. Meanwhile, load and unload other target # kernel modules while the livepatch transition is in progress. # -# - Load the "busy" kernel module, this time make it do 10 seconds worth -# of work. +# - Load the "busy" kernel module, this time make its work function loop # # - Meanwhile, the livepatch is loaded. Notice that the patch # transition does not complete as the targeted "busy" module is @@ -438,20 +434,23 @@ $MOD_TARGET_BUSY: ${MOD_TARGET_BUSY}_exit" echo -n "TEST: busy target module ... " dmesg -C -load_mod $MOD_TARGET_BUSY sleep_secs=10 +load_mod $MOD_TARGET_BUSY block_transition=Y load_lp_nowait $MOD_LIVEPATCH -# Don't wait for transition, load $MOD_TARGET while the transition -# is still stalled in $MOD_TARGET_BUSY::busymod_work_func() -sleep 5 + +# Wait until the livepatch reports in-transition state, i.e. that it's +# stalled on $MOD_TARGET_BUSY::busymod_work_func() +loop_until 'grep -q '^1$' /sys/kernel/livepatch/$MOD_LIVEPATCH/transition' || + die "failed to stall transition" + load_mod $MOD_TARGET unload_mod $MOD_TARGET disable_lp $MOD_LIVEPATCH unload_lp $MOD_LIVEPATCH unload_mod $MOD_TARGET_BUSY -check_result "% modprobe $MOD_TARGET_BUSY sleep_secs=10 +check_result "% modprobe $MOD_TARGET_BUSY block_transition=Y $MOD_TARGET_BUSY: ${MOD_TARGET_BUSY}_init -$MOD_TARGET_BUSY: busymod_work_func, sleeping 10 seconds ... +$MOD_TARGET_BUSY: busymod_work_func enter % modprobe $MOD_LIVEPATCH livepatch: enabling patch '$MOD_LIVEPATCH' livepatch: '$MOD_LIVEPATCH': initializing patching transition |