Hi Huacai,

On Tue, Oct 15, 2024 at 10:15:39AM +0800, Huacai Chen wrote:

I can take this patch to the loongarch tree, but I think others should get upstream via kselftests tree?

Yes, sounds good. Could you take a look at patches 2 and 4, too?

Thanks, Thomas

On Mon, Oct 14, 2024 at 7:36 PM Thomas Weißschuh thomas.weissschuh@linutronix.de wrote:

...

Not all tasks have a vDSO mapped, for example kthreads never do. If such a task ever ends up calling stack_top(), it will derefence the NULL vdso pointer and crash.

This can for example happen when using kunit:

    [<9000000000203874>] stack_top+0x58/0xa8
    [<90000000002956cc>] arch_pick_mmap_layout+0x164/0x220
    [<90000000003c284c>] kunit_vm_mmap_init+0x108/0x12c
    [<90000000003c1fbc>] __kunit_add_resource+0x38/0x8c
    [<90000000003c2704>] kunit_vm_mmap+0x88/0xc8
    [<9000000000410b14>] usercopy_test_init+0xbc/0x25c
    [<90000000003c1db4>] kunit_try_run_case+0x5c/0x184
    [<90000000003c3d54>] kunit_generic_run_threadfn_adapter+0x24/0x48
    [<900000000022e4bc>] kthread+0xc8/0xd4
    [<9000000000200ce8>] ret_from_kernel_thread+0xc/0xa4

Fixes: 803b0fc5c3f2 ("LoongArch: Add process management") Signed-off-by: Thomas Weißschuh thomas.weissschuh@linutronix.de

---

arch/loongarch/kernel/process.c | 16 +++++++++------- 1 file changed, 9 insertions(+), 7 deletions(-)

diff --git a/arch/loongarch/kernel/process.c b/arch/loongarch/kernel/process.c index f2ff8b5d591e4fd638109d2c98d75543c01a112c..6e58f65455c7ca3eae2e88ed852c8655a6701e5c 100644 --- a/arch/loongarch/kernel/process.c +++ b/arch/loongarch/kernel/process.c @@ -293,13 +293,15 @@ unsigned long stack_top(void) { unsigned long top = TASK_SIZE & PAGE_MASK;

•   /* Space for the VDSO & data page */
  

•   top -= PAGE_ALIGN(current->thread.vdso->size);
  

•   top -= VVAR_SIZE;
  

•   /* Space to randomize the VDSO base */
  

•   if (current->flags & PF_RANDOMIZE)
  

•           top -= VDSO_RANDOMIZE_SIZE;
  

•   if (current->thread.vdso) {
  

•           /* Space for the VDSO & data page */
  

•           top -= PAGE_ALIGN(current->thread.vdso->size);
  

•           top -= VVAR_SIZE;
  

•           /* Space to randomize the VDSO base */
  

•           if (current->flags & PF_RANDOMIZE)
  

•                   top -= VDSO_RANDOMIZE_SIZE;
  

•   }
  
    return top;
  

}

-- 2.47.0

On Mon, 14 Oct 2024 at 19:36, Thomas Weißschuh thomas.weissschuh@linutronix.de wrote:

Not all tasks have a vDSO mapped, for example kthreads never do. If such a task ever ends up calling stack_top(), it will derefence the NULL vdso pointer and crash.

This can for example happen when using kunit:

    [<9000000000203874>] stack_top+0x58/0xa8
    [<90000000002956cc>] arch_pick_mmap_layout+0x164/0x220
    [<90000000003c284c>] kunit_vm_mmap_init+0x108/0x12c
    [<90000000003c1fbc>] __kunit_add_resource+0x38/0x8c
    [<90000000003c2704>] kunit_vm_mmap+0x88/0xc8
    [<9000000000410b14>] usercopy_test_init+0xbc/0x25c
    [<90000000003c1db4>] kunit_try_run_case+0x5c/0x184
    [<90000000003c3d54>] kunit_generic_run_threadfn_adapter+0x24/0x48
    [<900000000022e4bc>] kthread+0xc8/0xd4
    [<9000000000200ce8>] ret_from_kernel_thread+0xc/0xa4

Fixes: 803b0fc5c3f2 ("LoongArch: Add process management") Signed-off-by: Thomas Weißschuh thomas.weissschuh@linutronix.de

---

Thanks very much for fixing this: the usercopy tests and kunit_vm_mmap stuff has been broken on quite a few architectures, so I really appreciate this being fixed "day one" for KUnit support. :-)

We'll take the rest of the patches via the kunit/kselftest tree; I agree that it makes more sense for this one to go in separately via loongarch.

Thanks, -- David

arch/loongarch/kernel/process.c | 16 +++++++++------- 1 file changed, 9 insertions(+), 7 deletions(-)

diff --git a/arch/loongarch/kernel/process.c b/arch/loongarch/kernel/process.c index f2ff8b5d591e4fd638109d2c98d75543c01a112c..6e58f65455c7ca3eae2e88ed852c8655a6701e5c 100644 --- a/arch/loongarch/kernel/process.c +++ b/arch/loongarch/kernel/process.c @@ -293,13 +293,15 @@ unsigned long stack_top(void) { unsigned long top = TASK_SIZE & PAGE_MASK;

•   /* Space for the VDSO & data page */
  

•   top -= PAGE_ALIGN(current->thread.vdso->size);
  

•   top -= VVAR_SIZE;
  

•   /* Space to randomize the VDSO base */
  

•   if (current->flags & PF_RANDOMIZE)
  

•           top -= VDSO_RANDOMIZE_SIZE;
  

•   if (current->thread.vdso) {
  

•           /* Space for the VDSO & data page */
  

•           top -= PAGE_ALIGN(current->thread.vdso->size);
  

•           top -= VVAR_SIZE;
  

•           /* Space to randomize the VDSO base */
  

•           if (current->flags & PF_RANDOMIZE)
  

•                   top -= VDSO_RANDOMIZE_SIZE;
  

•   }
  
    return top;
  

}

-- 2.47.0

Hi Thomas,

Thanks for work it out on LoongArch.

Reviewed-by: Bibo Mao maobibo@loongson.cn

On 2024/10/14 下午7:36, Thomas Weißschuh wrote:

Add a basic config to run kunit tests on LoongArch. This requires QEMU 9.1.0 or later for the necessary direct kernel boot support.

Signed-off-by: Thomas Weißschuh thomas.weissschuh@linutronix.de

tools/testing/kunit/qemu_configs/loongarch.py | 16 ++++++++++++++++ 1 file changed, 16 insertions(+)

diff --git a/tools/testing/kunit/qemu_configs/loongarch.py b/tools/testing/kunit/qemu_configs/loongarch.py new file mode 100644 index 0000000000000000000000000000000000000000..e7bb7c07819677dfdefac012821a732555813cae --- /dev/null +++ b/tools/testing/kunit/qemu_configs/loongarch.py @@ -0,0 +1,16 @@ +from ..qemu_config import QemuArchParams

+QEMU_ARCH = QemuArchParams(linux_arch='loongarch',

• 	   kconfig='''
  

+CONFIG_EFI_STUB=n +CONFIG_PCI_HOST_GENERIC=y +CONFIG_SERIAL_8250=y +CONFIG_SERIAL_8250_CONSOLE=y +CONFIG_SERIAL_OF_PLATFORM=y +''',

• 	   qemu_arch='loongarch64',
  

• 	   kernel_path='arch/loongarch/boot/vmlinux.elf',
  

• 	   kernel_command_line='console=ttyS0',
  

• 	   extra_qemu_params=[
  

• 			   '-machine', 'virt',
  

• 			   '-cpu', 'max',])
  
  

Hi Thomas,

On 10/14/24 05:36, Thomas Weißschuh wrote:

Add a basic config to run kunit tests on LoongArch. This requires QEMU 9.1.0 or later for the necessary direct kernel boot support.

Signed-off-by: Thomas Weißschuh thomas.weissschuh@linutronix.de

tools/testing/kunit/qemu_configs/loongarch.py | 16 ++++++++++++++++ 1 file changed, 16 insertions(+)

diff --git a/tools/testing/kunit/qemu_configs/loongarch.py b/tools/testing/kunit/qemu_configs/loongarch.py new file mode 100644 index 0000000000000000000000000000000000000000..e7bb7c07819677dfdefac012821a732555813cae --- /dev/null +++ b/tools/testing/kunit/qemu_configs/loongarch.py

Missing SPDX-License-Identifier.

@@ -0,0 +1,16 @@ +from ..qemu_config import QemuArchParams

+QEMU_ARCH = QemuArchParams(linux_arch='loongarch',

• 	   kconfig='''
  

+CONFIG_EFI_STUB=n +CONFIG_PCI_HOST_GENERIC=y +CONFIG_SERIAL_8250=y +CONFIG_SERIAL_8250_CONSOLE=y +CONFIG_SERIAL_OF_PLATFORM=y +''',

• 	   qemu_arch='loongarch64',
  

• 	   kernel_path='arch/loongarch/boot/vmlinux.elf',
  

• 	   kernel_command_line='console=ttyS0',
  

• 	   extra_qemu_params=[
  

• 			   '-machine', 'virt',
  

• 			   '-cpu', 'max',])
  
  

Please send v2 with all the reviewed by tags. If there is a resend 3.4 and 4/4 in this series, send them.

thanks, -- Shuah

On 10/17/24 14:31, Thomas Weißschuh wrote:

Hi Shuah,

Oct 17, 2024 22:27:29 Shuah Khan skhan@linuxfoundation.org:

...

On 10/14/24 05:36, Thomas Weißschuh wrote:

...

Add a basic config to run kunit tests on LoongArch. This requires QEMU 9.1.0 or later for the necessary direct kernel boot support. Signed-off-by: Thomas Weißschuh thomas.weissschuh@linutronix.de

---

tools/testing/kunit/qemu_configs/loongarch.py | 16 ++++++++++++++++   1 file changed, 16 insertions(+) diff --git a/tools/testing/kunit/qemu_configs/loongarch.py b/tools/testing/kunit/qemu_configs/loongarch.py new file mode 100644 index 0000000000000000000000000000000000000000..e7bb7c07819677dfdefac012821a732555813cae --- /dev/null +++ b/tools/testing/kunit/qemu_configs/loongarch.py

Missing SPDX-License-Identifier.

Tue others configs don't have one either.

...

...

@@ -0,0 +1,16 @@ +from ..qemu_config import QemuArchParams

+QEMU_ARCH = QemuArchParams(linux_arch='loongarch', +              kconfig=''' +CONFIG_EFI_STUB=n +CONFIG_PCI_HOST_GENERIC=y +CONFIG_SERIAL_8250=y +CONFIG_SERIAL_8250_CONSOLE=y +CONFIG_SERIAL_OF_PLATFORM=y +''', +              qemu_arch='loongarch64', +              kernel_path='arch/loongarch/boot/vmlinux.elf', +              kernel_command_line='console=ttyS0', +              extra_qemu_params=[ +                      '-machine', 'virt', +                      '-cpu', 'max',])

Please send v2 with all the reviewed by tags. If there is a resend 3.4 and 4/4 in this series, send them.

I'll do that. But it will take some weeks, as I just went on vacation.

Sounds good. Enjoy your vacation.

thanks, -- Shuah

On Mon, 14 Oct 2024 at 19:37, Thomas Weißschuh thomas.weissschuh@linutronix.de wrote:

Not all platforms support machine reboot. If it a proper reboot is not supported the machine will hang. Allow the QEMU configuration to override the necessary shutdown mode for the specific system under test.

Signed-off-by: Thomas Weißschuh thomas.weissschuh@linutronix.de

I suspect there's a cleaner way of doing this, but it'd involve changing all of the architectures over, so this looks good for now.

Reviewed-by: David Gow davidgow@google.com

Cheers, -- David

tools/testing/kunit/kunit_kernel.py | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/tools/testing/kunit/kunit_kernel.py b/tools/testing/kunit/kunit_kernel.py index 61931c4926fd6645f2c62dd13f9842a432ec4167..e76d7894b6c5195ece49f0d8c7ac35130df428a9 100644 --- a/tools/testing/kunit/kunit_kernel.py +++ b/tools/testing/kunit/kunit_kernel.py @@ -105,7 +105,9 @@ class LinuxSourceTreeOperationsQemu(LinuxSourceTreeOperations): self._kconfig = qemu_arch_params.kconfig self._qemu_arch = qemu_arch_params.qemu_arch self._kernel_path = qemu_arch_params.kernel_path

•           self._kernel_command_line = qemu_arch_params.kernel_command_line + ' kunit_shutdown=reboot'
  

•           self._kernel_command_line = qemu_arch_params.kernel_command_line
  

•           if 'kunit_shutdown=' not in self._kernel_command_line:
  

•                   self._kernel_command_line += ' kunit_shutdown=reboot'
            self._extra_qemu_params = qemu_arch_params.extra_qemu_params
            self._serial = qemu_arch_params.serial
  
  
  

-- 2.47.0

-- You received this message because you are subscribed to the Google Groups "KUnit Development" group. To unsubscribe from this group and stop receiving emails from it, send an email to kunit-dev+unsubscribe@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/kunit-dev/20241014-kunit-loongarch-v1-3-16....

Reviewed-by: Bibo Mao maobibo@loongson.cn

On 2024/10/14 下午7:36, Thomas Weißschuh wrote:

QEMU for LoongArch does not yet support shutdown/restart through ACPI. Use the pvpanic driver to enable shutdowns. This requires 9.1.0 for shutdown support in pvpanic, but that is the requirement of kunit on LoongArch anyways.

Signed-off-by: Thomas Weißschuh thomas.weissschuh@linutronix.de

tools/testing/kunit/qemu_configs/loongarch.py | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/tools/testing/kunit/qemu_configs/loongarch.py b/tools/testing/kunit/qemu_configs/loongarch.py index e7bb7c07819677dfdefac012821a732555813cae..1d2b780fbd5c0bde20aa6a5cd1217d0b3b443a93 100644 --- a/tools/testing/kunit/qemu_configs/loongarch.py +++ b/tools/testing/kunit/qemu_configs/loongarch.py @@ -4,13 +4,16 @@ QEMU_ARCH = QemuArchParams(linux_arch='loongarch', kconfig=''' CONFIG_EFI_STUB=n CONFIG_PCI_HOST_GENERIC=y +CONFIG_PVPANIC=y +CONFIG_PVPANIC_PCI=y CONFIG_SERIAL_8250=y CONFIG_SERIAL_8250_CONSOLE=y CONFIG_SERIAL_OF_PLATFORM=y ''', qemu_arch='loongarch64', kernel_path='arch/loongarch/boot/vmlinux.elf',

• 	   kernel_command_line='console=ttyS0',
  

• 	   kernel_command_line='console=ttyS0 kunit_shutdown=poweroff',
     extra_qemu_params=[
  		   '-machine', 'virt',
  

• 			   '-device', 'pvpanic-pci',
  		   '-cpu', 'max',])