| Message ID | 20240930-b4-slub-kunit-fix-v1-0-32ca9dbbbc11@suse.cz |
|---|---|
| Headers | show |
| Series | slub kunit tests fixes for 6.12 | expand |
On 9/30/24 01:37, Vlastimil Babka wrote: > Guenter Roeck reports that the new slub kunit tests added by commit > 4e1c44b3db79 ("kunit, slub: add test_kfree_rcu() and > test_leak_destroy()") cause a lockup on boot on several architectures > when the kunit tests are configured to be built-in and not modules. > > These tests invoke kfree_rcu() and kvfree_rcu_barrier() and boot > sequence inspection showed the runner for built-in kunit tests > kunit_run_all_tests() is called before setting system_state to > SYSTEM_RUNNING and calling rcu_end_inkernel_boot(), so this seems like a > likely cause. So while I was unable to reproduce the problem myself, > moving the call to kunit_run_all_tests() a bit later in the boot seems > to have fixed the lockup problem according to Guenter's limited testing. > > No kunit tests should be broken by calling the built-in executor a bit > later, as when compiled as modules, they are still executed even later > than this. > > Fixes: 4e1c44b3db79 ("kunit, slub: add test_kfree_rcu() and test_leak_destroy()") > Reported-by: Guenter Roeck <linux@roeck-us.net> > Closes: https://lore.kernel.org/all/6fcb1252-7990-4f0d-8027-5e83f0fb9409@roeck-us.net/ > Cc: "Paul E. McKenney" <paulmck@kernel.org> > Cc: Boqun Feng <boqun.feng@gmail.com> > Cc: Uladzislau Rezki <urezki@gmail.com> > Cc: rcu@vger.kernel.org > Cc: Brendan Higgins <brendanhiggins@google.com> > Cc: David Gow <davidgow@google.com> > Cc: Rae Moar <rmoar@google.com> > Cc: linux-kselftest@vger.kernel.org > Cc: kunit-dev@googlegroups.com > Signed-off-by: Vlastimil Babka <vbabka@suse.cz> > --- > init/main.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/init/main.c b/init/main.c > index c4778edae7972f512d5eefe8400075ac35a70d1c..7890ebb00e84b8bd7bac28923fb1fe571b3e9ee2 100644 > --- a/init/main.c > +++ b/init/main.c > @@ -1489,6 +1489,8 @@ static int __ref kernel_init(void *unused) > > rcu_end_inkernel_boot(); > > + kunit_run_all_tests(); > + > do_sysctl_args(); > > if (ramdisk_execute_command) { > @@ -1579,8 +1581,6 @@ static noinline void __init kernel_init_freeable(void) > > do_basic_setup(); > > - kunit_run_all_tests(); > - > wait_for_initramfs(); > console_on_rootfs(); > > Unfortunately it doesn't work. With this patch applied, I get many backtraces similar to the following, and ultimately the image crashes. This is with arm64. I do not see the problem if I drop this patch. Guenter --- [ 9.465871] KTAP version 1 [ 9.465964] # Subtest: iov_iter [ 9.466056] # module: kunit_iov_iter [ 9.466115] 1..12 [ 9.467000] Unable to handle kernel paging request at virtual address ffffc37db5c9f26c [ 9.467244] Mem abort info: [ 9.467332] ESR = 0x0000000086000007 [ 9.467454] EC = 0x21: IABT (current EL), IL = 32 bits [ 9.467576] SET = 0, FnV = 0 [ 9.467667] EA = 0, S1PTW = 0 [ 9.467762] FSC = 0x07: level 3 translation fault [ 9.467912] swapper pgtable: 4k pages, 48-bit VAs, pgdp=0000000042a59000 [ 9.468055] [ffffc37db5c9f26c] pgd=0000000000000000, p4d=1000000044b36003, pud=1000000044b37003, pmd=1000000044b3a003, pte=0000000000000000 [ 9.469430] Internal error: Oops: 0000000086000007 [#1] PREEMPT SMP [ 9.469687] Modules linked in: [ 9.470035] CPU: 0 UID: 0 PID: 550 Comm: kunit_try_catch Tainted: G N 6.12.0-rc1-00005-ga65e3eb58cdb #1 [ 9.470290] Tainted: [N]=TEST [ 9.470356] Hardware name: linux,dummy-virt (DT) [ 9.470530] pstate: 80000005 (Nzcv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ 9.470656] pc : iov_kunit_copy_to_kvec+0x0/0x334 [ 9.471055] lr : kunit_try_run_case+0x6c/0x15c [ 9.471145] sp : ffff800080883de0 [ 9.471210] x29: ffff800080883e20 x28: 0000000000000000 x27: 0000000000000000 [ 9.471376] x26: 0000000000000000 x25: 0000000000000000 x24: ffff80008000bb68 [ 9.471501] x23: ffffc37db3f7093c x22: ffff80008000b940 x21: ffff545847af4c00 [ 9.471622] x20: ffff545847cd3940 x19: ffff80008000bb50 x18: 0000000000000006 [ 9.471742] x17: 6c61746f7420303a x16: 70696b7320303a6c x15: 0000000000000172 [ 9.471863] x14: 0000000000020000 x13: 0000000000000000 x12: ffffc37db6a600c8 [ 9.471983] x11: 0000000000000043 x10: 0000000000000043 x9 : 1fffffffffffffff [ 9.472122] x8 : 00000000ffffffff x7 : 000000001040d4fd x6 : ffffc37db70c3810 [ 9.472243] x5 : 0000000000000000 x4 : ffffffffc4653600 x3 : 000000003b9ac9ff [ 9.472363] x2 : 0000000000000001 x1 : ffffc37db5c9f26c x0 : ffff80008000bb50 [ 9.472572] Call trace: [ 9.472636] iov_kunit_copy_to_kvec+0x0/0x334 [ 9.472740] kunit_generic_run_threadfn_adapter+0x28/0x4c [ 9.472835] kthread+0x11c/0x120 [ 9.472903] ret_from_fork+0x10/0x20 [ 9.473146] Code: ???????? ???????? ???????? ???????? (????????) [ 9.473505] ---[ end trace 0000000000000000 ]---
On 9/30/24 11:50, Guenter Roeck wrote: > On 9/30/24 01:37, Vlastimil Babka wrote: >> Guenter Roeck reports that the new slub kunit tests added by commit >> 4e1c44b3db79 ("kunit, slub: add test_kfree_rcu() and >> test_leak_destroy()") cause a lockup on boot on several architectures >> when the kunit tests are configured to be built-in and not modules. >> >> These tests invoke kfree_rcu() and kvfree_rcu_barrier() and boot >> sequence inspection showed the runner for built-in kunit tests >> kunit_run_all_tests() is called before setting system_state to >> SYSTEM_RUNNING and calling rcu_end_inkernel_boot(), so this seems like a >> likely cause. So while I was unable to reproduce the problem myself, >> moving the call to kunit_run_all_tests() a bit later in the boot seems >> to have fixed the lockup problem according to Guenter's limited testing. >> >> No kunit tests should be broken by calling the built-in executor a bit >> later, as when compiled as modules, they are still executed even later >> than this. >> Actually, that is wrong. Turns out kunit_iov_iter (and other kunit tests) are marked __init. That means those unit tests have to run before the init code is released, and it actually _is_ harmful to run the tests after rcu_end_inkernel_boot() because at that time free_initmem() has already been called. Guenter >> Fixes: 4e1c44b3db79 ("kunit, slub: add test_kfree_rcu() and test_leak_destroy()") >> Reported-by: Guenter Roeck <linux@roeck-us.net> >> Closes: https://lore.kernel.org/all/6fcb1252-7990-4f0d-8027-5e83f0fb9409@roeck-us.net/ >> Cc: "Paul E. McKenney" <paulmck@kernel.org> >> Cc: Boqun Feng <boqun.feng@gmail.com> >> Cc: Uladzislau Rezki <urezki@gmail.com> >> Cc: rcu@vger.kernel.org >> Cc: Brendan Higgins <brendanhiggins@google.com> >> Cc: David Gow <davidgow@google.com> >> Cc: Rae Moar <rmoar@google.com> >> Cc: linux-kselftest@vger.kernel.org >> Cc: kunit-dev@googlegroups.com >> Signed-off-by: Vlastimil Babka <vbabka@suse.cz> >> --- >> init/main.c | 4 ++-- >> 1 file changed, 2 insertions(+), 2 deletions(-) >> >> diff --git a/init/main.c b/init/main.c >> index c4778edae7972f512d5eefe8400075ac35a70d1c..7890ebb00e84b8bd7bac28923fb1fe571b3e9ee2 100644 >> --- a/init/main.c >> +++ b/init/main.c >> @@ -1489,6 +1489,8 @@ static int __ref kernel_init(void *unused) >> rcu_end_inkernel_boot(); >> + kunit_run_all_tests(); >> + >> do_sysctl_args(); >> if (ramdisk_execute_command) { >> @@ -1579,8 +1581,6 @@ static noinline void __init kernel_init_freeable(void) >> do_basic_setup(); >> - kunit_run_all_tests(); >> - >> wait_for_initramfs(); >> console_on_rootfs(); >> > Unfortunately it doesn't work. With this patch applied, I get many backtraces > similar to the following, and ultimately the image crashes. This is with arm64. > I do not see the problem if I drop this patch. > > Guenter > > --- > [ 9.465871] KTAP version 1 > [ 9.465964] # Subtest: iov_iter > [ 9.466056] # module: kunit_iov_iter > [ 9.466115] 1..12 > [ 9.467000] Unable to handle kernel paging request at virtual address ffffc37db5c9f26c > [ 9.467244] Mem abort info: > [ 9.467332] ESR = 0x0000000086000007 > [ 9.467454] EC = 0x21: IABT (current EL), IL = 32 bits > [ 9.467576] SET = 0, FnV = 0 > [ 9.467667] EA = 0, S1PTW = 0 > [ 9.467762] FSC = 0x07: level 3 translation fault > [ 9.467912] swapper pgtable: 4k pages, 48-bit VAs, pgdp=0000000042a59000 > [ 9.468055] [ffffc37db5c9f26c] pgd=0000000000000000, p4d=1000000044b36003, pud=1000000044b37003, pmd=1000000044b3a003, pte=0000000000000000 > [ 9.469430] Internal error: Oops: 0000000086000007 [#1] PREEMPT SMP > [ 9.469687] Modules linked in: > [ 9.470035] CPU: 0 UID: 0 PID: 550 Comm: kunit_try_catch Tainted: G N 6.12.0-rc1-00005-ga65e3eb58cdb #1 > [ 9.470290] Tainted: [N]=TEST > [ 9.470356] Hardware name: linux,dummy-virt (DT) > [ 9.470530] pstate: 80000005 (Nzcv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) > [ 9.470656] pc : iov_kunit_copy_to_kvec+0x0/0x334 > [ 9.471055] lr : kunit_try_run_case+0x6c/0x15c > [ 9.471145] sp : ffff800080883de0 > [ 9.471210] x29: ffff800080883e20 x28: 0000000000000000 x27: 0000000000000000 > [ 9.471376] x26: 0000000000000000 x25: 0000000000000000 x24: ffff80008000bb68 > [ 9.471501] x23: ffffc37db3f7093c x22: ffff80008000b940 x21: ffff545847af4c00 > [ 9.471622] x20: ffff545847cd3940 x19: ffff80008000bb50 x18: 0000000000000006 > [ 9.471742] x17: 6c61746f7420303a x16: 70696b7320303a6c x15: 0000000000000172 > [ 9.471863] x14: 0000000000020000 x13: 0000000000000000 x12: ffffc37db6a600c8 > [ 9.471983] x11: 0000000000000043 x10: 0000000000000043 x9 : 1fffffffffffffff > [ 9.472122] x8 : 00000000ffffffff x7 : 000000001040d4fd x6 : ffffc37db70c3810 > [ 9.472243] x5 : 0000000000000000 x4 : ffffffffc4653600 x3 : 000000003b9ac9ff > [ 9.472363] x2 : 0000000000000001 x1 : ffffc37db5c9f26c x0 : ffff80008000bb50 > [ 9.472572] Call trace: > [ 9.472636] iov_kunit_copy_to_kvec+0x0/0x334 > [ 9.472740] kunit_generic_run_threadfn_adapter+0x28/0x4c > [ 9.472835] kthread+0x11c/0x120 > [ 9.472903] ret_from_fork+0x10/0x20 > [ 9.473146] Code: ???????? ???????? ???????? ???????? (????????) > [ 9.473505] ---[ end trace 0000000000000000 ]--- >
On 10/1/24 1:55 AM, Guenter Roeck wrote: > On 9/30/24 11:50, Guenter Roeck wrote: >> On 9/30/24 01:37, Vlastimil Babka wrote: >>> Guenter Roeck reports that the new slub kunit tests added by commit >>> 4e1c44b3db79 ("kunit, slub: add test_kfree_rcu() and >>> test_leak_destroy()") cause a lockup on boot on several architectures >>> when the kunit tests are configured to be built-in and not modules. >>> >>> These tests invoke kfree_rcu() and kvfree_rcu_barrier() and boot >>> sequence inspection showed the runner for built-in kunit tests >>> kunit_run_all_tests() is called before setting system_state to >>> SYSTEM_RUNNING and calling rcu_end_inkernel_boot(), so this seems like a >>> likely cause. So while I was unable to reproduce the problem myself, >>> moving the call to kunit_run_all_tests() a bit later in the boot seems >>> to have fixed the lockup problem according to Guenter's limited testing. >>> >>> No kunit tests should be broken by calling the built-in executor a bit >>> later, as when compiled as modules, they are still executed even later >>> than this. >>> > > Actually, that is wrong. > > Turns out kunit_iov_iter (and other kunit tests) are marked __init. > That means those unit tests have to run before the init code is released, > and it actually _is_ harmful to run the tests after rcu_end_inkernel_boot() > because at that time free_initmem() has already been called. Oh, guess that explains why the kunit_run_all_tests() executor is called so suspiciously early. Of course when built as modules, __init has a different lifetime. Guess I will just skip the two new tests using kfree_rcu() when the slub kunit is built-in then. Thanks for testing. > Guenter > >>> Fixes: 4e1c44b3db79 ("kunit, slub: add test_kfree_rcu() and >>> test_leak_destroy()") >>> Reported-by: Guenter Roeck <linux@roeck-us.net> >>> Closes: >>> https://lore.kernel.org/all/6fcb1252-7990-4f0d-8027-5e83f0fb9409@roeck-us.net/ >>> Cc: "Paul E. McKenney" <paulmck@kernel.org> >>> Cc: Boqun Feng <boqun.feng@gmail.com> >>> Cc: Uladzislau Rezki <urezki@gmail.com> >>> Cc: rcu@vger.kernel.org >>> Cc: Brendan Higgins <brendanhiggins@google.com> >>> Cc: David Gow <davidgow@google.com> >>> Cc: Rae Moar <rmoar@google.com> >>> Cc: linux-kselftest@vger.kernel.org >>> Cc: kunit-dev@googlegroups.com >>> Signed-off-by: Vlastimil Babka <vbabka@suse.cz> >>> --- >>> init/main.c | 4 ++-- >>> 1 file changed, 2 insertions(+), 2 deletions(-) >>> >>> diff --git a/init/main.c b/init/main.c >>> index >>> c4778edae7972f512d5eefe8400075ac35a70d1c..7890ebb00e84b8bd7bac28923fb1fe571b3e9ee2 100644 >>> --- a/init/main.c >>> +++ b/init/main.c >>> @@ -1489,6 +1489,8 @@ static int __ref kernel_init(void *unused) >>> rcu_end_inkernel_boot(); >>> + kunit_run_all_tests(); >>> + >>> do_sysctl_args(); >>> if (ramdisk_execute_command) { >>> @@ -1579,8 +1581,6 @@ static noinline void __init >>> kernel_init_freeable(void) >>> do_basic_setup(); >>> - kunit_run_all_tests(); >>> - >>> wait_for_initramfs(); >>> console_on_rootfs(); >>> >> Unfortunately it doesn't work. With this patch applied, I get many >> backtraces >> similar to the following, and ultimately the image crashes. This is >> with arm64. >> I do not see the problem if I drop this patch. >> >> Guenter >> >> --- >> [ 9.465871] KTAP version 1 >> [ 9.465964] # Subtest: iov_iter >> [ 9.466056] # module: kunit_iov_iter >> [ 9.466115] 1..12 >> [ 9.467000] Unable to handle kernel paging request at virtual >> address ffffc37db5c9f26c >> [ 9.467244] Mem abort info: >> [ 9.467332] ESR = 0x0000000086000007 >> [ 9.467454] EC = 0x21: IABT (current EL), IL = 32 bits >> [ 9.467576] SET = 0, FnV = 0 >> [ 9.467667] EA = 0, S1PTW = 0 >> [ 9.467762] FSC = 0x07: level 3 translation fault >> [ 9.467912] swapper pgtable: 4k pages, 48-bit VAs, >> pgdp=0000000042a59000 >> [ 9.468055] [ffffc37db5c9f26c] pgd=0000000000000000, >> p4d=1000000044b36003, pud=1000000044b37003, pmd=1000000044b3a003, >> pte=0000000000000000 >> [ 9.469430] Internal error: Oops: 0000000086000007 [#1] PREEMPT SMP >> [ 9.469687] Modules linked in: >> [ 9.470035] CPU: 0 UID: 0 PID: 550 Comm: kunit_try_catch Tainted: >> G N 6.12.0-rc1-00005-ga65e3eb58cdb #1 >> [ 9.470290] Tainted: [N]=TEST >> [ 9.470356] Hardware name: linux,dummy-virt (DT) >> [ 9.470530] pstate: 80000005 (Nzcv daif -PAN -UAO -TCO -DIT -SSBS >> BTYPE=--) >> [ 9.470656] pc : iov_kunit_copy_to_kvec+0x0/0x334 >> [ 9.471055] lr : kunit_try_run_case+0x6c/0x15c >> [ 9.471145] sp : ffff800080883de0 >> [ 9.471210] x29: ffff800080883e20 x28: 0000000000000000 x27: >> 0000000000000000 >> [ 9.471376] x26: 0000000000000000 x25: 0000000000000000 x24: >> ffff80008000bb68 >> [ 9.471501] x23: ffffc37db3f7093c x22: ffff80008000b940 x21: >> ffff545847af4c00 >> [ 9.471622] x20: ffff545847cd3940 x19: ffff80008000bb50 x18: >> 0000000000000006 >> [ 9.471742] x17: 6c61746f7420303a x16: 70696b7320303a6c x15: >> 0000000000000172 >> [ 9.471863] x14: 0000000000020000 x13: 0000000000000000 x12: >> ffffc37db6a600c8 >> [ 9.471983] x11: 0000000000000043 x10: 0000000000000043 x9 : >> 1fffffffffffffff >> [ 9.472122] x8 : 00000000ffffffff x7 : 000000001040d4fd x6 : >> ffffc37db70c3810 >> [ 9.472243] x5 : 0000000000000000 x4 : ffffffffc4653600 x3 : >> 000000003b9ac9ff >> [ 9.472363] x2 : 0000000000000001 x1 : ffffc37db5c9f26c x0 : >> ffff80008000bb50 >> [ 9.472572] Call trace: >> [ 9.472636] iov_kunit_copy_to_kvec+0x0/0x334 >> [ 9.472740] kunit_generic_run_threadfn_adapter+0x28/0x4c >> [ 9.472835] kthread+0x11c/0x120 >> [ 9.472903] ret_from_fork+0x10/0x20 >> [ 9.473146] Code: ???????? ???????? ???????? ???????? (????????) >> [ 9.473505] ---[ end trace 0000000000000000 ]--- >> >
On Tue, 1 Oct 2024 at 07:55, Guenter Roeck <linux@roeck-us.net> wrote: > > On 9/30/24 11:50, Guenter Roeck wrote: > > On 9/30/24 01:37, Vlastimil Babka wrote: > >> Guenter Roeck reports that the new slub kunit tests added by commit > >> 4e1c44b3db79 ("kunit, slub: add test_kfree_rcu() and > >> test_leak_destroy()") cause a lockup on boot on several architectures > >> when the kunit tests are configured to be built-in and not modules. > >> > >> These tests invoke kfree_rcu() and kvfree_rcu_barrier() and boot > >> sequence inspection showed the runner for built-in kunit tests > >> kunit_run_all_tests() is called before setting system_state to > >> SYSTEM_RUNNING and calling rcu_end_inkernel_boot(), so this seems like a > >> likely cause. So while I was unable to reproduce the problem myself, > >> moving the call to kunit_run_all_tests() a bit later in the boot seems > >> to have fixed the lockup problem according to Guenter's limited testing. > >> > >> No kunit tests should be broken by calling the built-in executor a bit > >> later, as when compiled as modules, they are still executed even later > >> than this. > >> > > Actually, that is wrong. > > Turns out kunit_iov_iter (and other kunit tests) are marked __init. > That means those unit tests have to run before the init code is released, > and it actually _is_ harmful to run the tests after rcu_end_inkernel_boot() > because at that time free_initmem() has already been called. Yeah: some tests are marked __init. KUnit does actually mark these with an attribute, so we can potentially split the execution up into an 'init' part which runs early, and a later part, but there are some complications if we still want to track the total number of tests and support filtering, etc. properly. That's something I think we'll look at for 6.13: in the meantime, skipping the problematic slub tests when built-in seems to be the right short-term fix. I'll look into having the built-in executor moved later for non-init tests once we've worked out how best to adapt the filter/KTAP output code to do so as cleanly as possible. Cheers, -- David > > Guenter > > >> Fixes: 4e1c44b3db79 ("kunit, slub: add test_kfree_rcu() and test_leak_destroy()") > >> Reported-by: Guenter Roeck <linux@roeck-us.net> > >> Closes: https://lore.kernel.org/all/6fcb1252-7990-4f0d-8027-5e83f0fb9409@roeck-us.net/ > >> Cc: "Paul E. McKenney" <paulmck@kernel.org> > >> Cc: Boqun Feng <boqun.feng@gmail.com> > >> Cc: Uladzislau Rezki <urezki@gmail.com> > >> Cc: rcu@vger.kernel.org > >> Cc: Brendan Higgins <brendanhiggins@google.com> > >> Cc: David Gow <davidgow@google.com> > >> Cc: Rae Moar <rmoar@google.com> > >> Cc: linux-kselftest@vger.kernel.org > >> Cc: kunit-dev@googlegroups.com > >> Signed-off-by: Vlastimil Babka <vbabka@suse.cz> > >> --- > >> init/main.c | 4 ++-- > >> 1 file changed, 2 insertions(+), 2 deletions(-) > >> > >> diff --git a/init/main.c b/init/main.c > >> index c4778edae7972f512d5eefe8400075ac35a70d1c..7890ebb00e84b8bd7bac28923fb1fe571b3e9ee2 100644 > >> --- a/init/main.c > >> +++ b/init/main.c > >> @@ -1489,6 +1489,8 @@ static int __ref kernel_init(void *unused) > >> rcu_end_inkernel_boot(); > >> + kunit_run_all_tests(); > >> + > >> do_sysctl_args(); > >> if (ramdisk_execute_command) { > >> @@ -1579,8 +1581,6 @@ static noinline void __init kernel_init_freeable(void) > >> do_basic_setup(); > >> - kunit_run_all_tests(); > >> - > >> wait_for_initramfs(); > >> console_on_rootfs(); > >> > > Unfortunately it doesn't work. With this patch applied, I get many backtraces > > similar to the following, and ultimately the image crashes. This is with arm64. > > I do not see the problem if I drop this patch. > > > > Guenter > > > > --- > > [ 9.465871] KTAP version 1 > > [ 9.465964] # Subtest: iov_iter > > [ 9.466056] # module: kunit_iov_iter > > [ 9.466115] 1..12 > > [ 9.467000] Unable to handle kernel paging request at virtual address ffffc37db5c9f26c > > [ 9.467244] Mem abort info: > > [ 9.467332] ESR = 0x0000000086000007 > > [ 9.467454] EC = 0x21: IABT (current EL), IL = 32 bits > > [ 9.467576] SET = 0, FnV = 0 > > [ 9.467667] EA = 0, S1PTW = 0 > > [ 9.467762] FSC = 0x07: level 3 translation fault > > [ 9.467912] swapper pgtable: 4k pages, 48-bit VAs, pgdp=0000000042a59000 > > [ 9.468055] [ffffc37db5c9f26c] pgd=0000000000000000, p4d=1000000044b36003, pud=1000000044b37003, pmd=1000000044b3a003, pte=0000000000000000 > > [ 9.469430] Internal error: Oops: 0000000086000007 [#1] PREEMPT SMP > > [ 9.469687] Modules linked in: > > [ 9.470035] CPU: 0 UID: 0 PID: 550 Comm: kunit_try_catch Tainted: G N 6.12.0-rc1-00005-ga65e3eb58cdb #1 > > [ 9.470290] Tainted: [N]=TEST > > [ 9.470356] Hardware name: linux,dummy-virt (DT) > > [ 9.470530] pstate: 80000005 (Nzcv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) > > [ 9.470656] pc : iov_kunit_copy_to_kvec+0x0/0x334 > > [ 9.471055] lr : kunit_try_run_case+0x6c/0x15c > > [ 9.471145] sp : ffff800080883de0 > > [ 9.471210] x29: ffff800080883e20 x28: 0000000000000000 x27: 0000000000000000 > > [ 9.471376] x26: 0000000000000000 x25: 0000000000000000 x24: ffff80008000bb68 > > [ 9.471501] x23: ffffc37db3f7093c x22: ffff80008000b940 x21: ffff545847af4c00 > > [ 9.471622] x20: ffff545847cd3940 x19: ffff80008000bb50 x18: 0000000000000006 > > [ 9.471742] x17: 6c61746f7420303a x16: 70696b7320303a6c x15: 0000000000000172 > > [ 9.471863] x14: 0000000000020000 x13: 0000000000000000 x12: ffffc37db6a600c8 > > [ 9.471983] x11: 0000000000000043 x10: 0000000000000043 x9 : 1fffffffffffffff > > [ 9.472122] x8 : 00000000ffffffff x7 : 000000001040d4fd x6 : ffffc37db70c3810 > > [ 9.472243] x5 : 0000000000000000 x4 : ffffffffc4653600 x3 : 000000003b9ac9ff > > [ 9.472363] x2 : 0000000000000001 x1 : ffffc37db5c9f26c x0 : ffff80008000bb50 > > [ 9.472572] Call trace: > > [ 9.472636] iov_kunit_copy_to_kvec+0x0/0x334 > > [ 9.472740] kunit_generic_run_threadfn_adapter+0x28/0x4c > > [ 9.472835] kthread+0x11c/0x120 > > [ 9.472903] ret_from_fork+0x10/0x20 > > [ 9.473146] Code: ???????? ???????? ???????? ???????? (????????) > > [ 9.473505] ---[ end trace 0000000000000000 ]--- > > >
The SLUB changes for 6.12 included new kunit tests that resulted in noisy warnings, which we normally suppress, and a boot lockup in some configurations in case the kunit tests are built-in. The warnings are addressed in Patch 1. The lockups I couldn't reproduce, but inspecting boot initialization order makes me suspect the tests (which call few RCU operations) are being executed a bit too early before RCU finishes initialization. Moving the exection later seems to do the trick, so I'd like to ask kunit folks to ack this change (Patch 2). If RCU folks have any insights, it would be welcome too. So these are now fixes for 4e1c44b3db79 ("kunit, slub: add test_kfree_rcu() and test_leak_destroy()") Once sent as a full patch, I also want to include comment fixes from Ulad for kvfree_rcu_queue_batch(): https://lore.kernel.org/all/CA%2BKHdyV%3D0dpJX_v_tcuTQ-_ree-Yb9ch3F_HqfT4YnH8%3DzyWng@mail.gmail.com/ The plan is to take the fixes via slab tree for a 6.12 rcX. Signed-off-by: Vlastimil Babka <vbabka@suse.cz> --- Vlastimil Babka (2): mm, slab: suppress warnings in test_leak_destroy kunit test kunit: move call to kunit_run_all_tests() after rcu_end_inkernel_boot() init/main.c | 4 ++-- lib/slub_kunit.c | 4 ++-- mm/slab.h | 6 ++++++ mm/slab_common.c | 5 +++-- mm/slub.c | 5 +++-- 5 files changed, 16 insertions(+), 8 deletions(-) --- base-commit: 9852d85ec9d492ebef56dc5f229416c925758edc change-id: 20240930-b4-slub-kunit-fix-6fba4d1c1742 Best regards,