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charset=us-ascii Content-Disposition: inline In-Reply-To: <20240314094045.157149-1-usama.anjum@collabora.com> X-Stat-Signature: 8b8734dixinrqx4t3h1micyg3gfbaopm X-Rspamd-Queue-Id: AAA491A001E X-Rspamd-Server: rspam02 X-Rspam-User: X-HE-Tag: 1713444779-237530 X-HE-Meta: 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 WXFDU9LV q/gm3laFxdQp5+60gJ/ixZ7qgZ9sngj3O0KI+/3fL4LD7euc855p9pezIPgO7Y+1RGJmoSCaaPIPuLVKOZm2/wIGlzxoJFrioE4gGzCTwvSNz33n5MPw+qrOmJHlBBBe1Yzx+clbFuXAgGBZC5xExdGeA8lOcbM0T0f/0cuYeXgxYeVZzkDq9+8FDcQWT/MdzABtLmndRJm+xlxRpMl0Qnzc7cNzMFcrSL/h9 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: Hi again, On Thu, Mar 14, 2024 at 02:40:45PM +0500, Muhammad Usama Anjum wrote: > The atexit() is called from parent process as well as forked processes. > Hence the child restores the settings at exit while the parent is still > executing. Fix this by checking pid of atexit() calling process and only > restore THP number from parent process. > > Fixes: c23ea61726d5 ("selftests/mm: protection_keys: save/restore nr_hugepages settings") > Tested-by: Joey Gouly > Signed-off-by: Muhammad Usama Anjum > --- > tools/testing/selftests/mm/protection_keys.c | 6 +++++- > 1 file changed, 5 insertions(+), 1 deletion(-) > > diff --git a/tools/testing/selftests/mm/protection_keys.c b/tools/testing/selftests/mm/protection_keys.c > index f822ae31af22e..374a308174d2b 100644 > --- a/tools/testing/selftests/mm/protection_keys.c > +++ b/tools/testing/selftests/mm/protection_keys.c > @@ -1745,9 +1745,12 @@ void pkey_setup_shadow(void) > shadow_pkey_reg = __read_pkey_reg(); > } > > +pid_t parent_pid; > + > void restore_settings_atexit(void) > { > - cat_into_file(buf, "/proc/sys/vm/nr_hugepages"); > + if (parent_pid == getpid()) > + cat_into_file(buf, "/proc/sys/vm/nr_hugepages"); > } > > void save_settings(void) > @@ -1773,6 +1776,7 @@ void save_settings(void) > exit(__LINE__); > } > > + parent_pid = getpid(); > atexit(restore_settings_atexit); > close(fd); > } After more testing, this is not actually enough. It passes sometimes, which is why I gave my Tested-by, but it can still fail the same way as I originally said. assert() at protection_keys.c::812 test_nr: 19 iteration: 1 running abort_hooks()... errno at assert: 12 I think the parent process needs to wait for all it's child processes (recursively). This is due to the test_pkey_alloc_exhaust() calling become_child(), where it exits, and that exit may be from the original PID. Thanks, Joey