There is quite a bit of tribal knowledge around proper use of
try_module_get() and that it must be used only in a context which
can ensure the module won't be gone during the operation. Document
this little bit of tribal knowledge.
Signed-off-by: Luis Chamberlain <mcgrof(a)kernel.org>
---
kernel/module.c | 22 ++++++++++++++++++++++
1 file changed, 22 insertions(+)
diff --git a/kernel/module.c b/kernel/module.c
index ed13917ea5f3..0d609647a54d 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -1066,6 +1066,28 @@ void __module_get(struct module *module)
}
EXPORT_SYMBOL(__module_get);
+/**
+ * try_module_get - yields to module removal and bumps reference count otherwise
+ * @module: the module we should check for
+ *
+ * This can be used to check if userspace has requested to remove a module,
+ * and if so let the caller give up. Otherwise it takes a reference count to
+ * ensure a request from userspace to remove the module cannot happen.
+ *
+ * Care must be taken to ensure the module cannot be removed during
+ * try_module_get(). This can be done by having another entity other than the
+ * module itself increment the module reference count, or through some other
+ * means which gaurantees the module could not be removed during an operation.
+ * An example of this later case is using this call in a sysfs file which the
+ * module created. The sysfs store / read file operation is ensured to exist
+ * and still be present by kernfs's active reference. If a sysfs file operation
+ * is being run, the module which created it must still exist as the module is
+ * in charge of removal of the sysfs file.
+ *
+ * The real value to try_module_get() is the module_is_live() check which
+ * ensures this the caller of try_module_get() can yields to userspace module
+ * removal requests and fail whatever it was about to process.
+ */
bool try_module_get(struct module *module)
{
bool ret = true;
--
2.30.2
The XSAVE feature set supports the saving and restoring of state components
such as FPU, which is used for process context switching.
In order to ensure that XSAVE works correctly, add XSAVE basic test for
XSAVE architecture functionality.
This patch set tests XSAVE/XRSTOR instructions on x86 platforms and verify if
the XSAVE/XRSTOR works correctly during signal handling.
Cases such as signal handling, process creation, other xstate(except FPU)
tests for XSAVE check, etc. will be added to the Linux kernel self-test.
If appropriate, it is even planned to add the [1] mentioned XSAVE issues
reproduce and some XSAVE anomaly tests to the kernel self-test.
[1]: https://lore.kernel.org/lkml/0000000000004c453905c30f8334@google.com/
Pengfei Xu (2):
selftests/xsave: test basic XSAVE architecture functionality
selftests/xsave: add xsave test during signal handling
tools/testing/selftests/Makefile | 1 +
tools/testing/selftests/xsave/.gitignore | 3 +
tools/testing/selftests/xsave/Makefile | 6 +
tools/testing/selftests/xsave/xsave_common.h | 246 ++++++++++++++++++
.../selftests/xsave/xsave_instruction.c | 83 ++++++
.../selftests/xsave/xsave_signal_handle.c | 184 +++++++++++++
6 files changed, 523 insertions(+)
create mode 100644 tools/testing/selftests/xsave/.gitignore
create mode 100644 tools/testing/selftests/xsave/Makefile
create mode 100644 tools/testing/selftests/xsave/xsave_common.h
create mode 100644 tools/testing/selftests/xsave/xsave_instruction.c
create mode 100644 tools/testing/selftests/xsave/xsave_signal_handle.c
--
2.20.1
This v2 rebases onto the latest linux-next tag, next-20210701. A few
changes were needed, namely:
1) changes kernfs_init_failure_injection() to return int instead
of void. On the latest linux-next we have a new static build
check for this, so this mistake was captured when building.
2) I made kernfs_init_failure_injection static
3) lib/test_sysfs.c moved to the new blk_alloc_disk() added by
Christoph as direct queue allocation is no longer supported,
ie, blk_alloc_queue() is no longer exported. This work was
done by Christoph in preparation to help make add_disk*()
callers eventually return an error code and make the error
handling much saner. Because of this same change
blk_cleanup_queue() is no longer needed so we embrace
the shiny new blk_cleanup_disk().
I've put this up on my linux-next git tree [0] under the branch
named 20210701-sysfs-fix-races-v2.
[0] https://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux-next.git/log/?…
Luis Chamberlain (4):
selftests: add tests_sysfs module
kernfs: add initial failure injection support
test_sysfs: add support to use kernfs failure injection
test_sysfs: demonstrate deadlock fix
.../fault-injection/fault-injection.rst | 22 +
MAINTAINERS | 9 +-
fs/kernfs/Makefile | 1 +
fs/kernfs/failure-injection.c | 83 +
fs/kernfs/file.c | 13 +
fs/kernfs/kernfs-internal.h | 72 +
include/linux/kernfs.h | 5 +
lib/Kconfig.debug | 23 +
lib/Makefile | 1 +
lib/test_sysfs.c | 1027 ++++++++++++
tools/testing/selftests/sysfs/Makefile | 12 +
tools/testing/selftests/sysfs/config | 5 +
tools/testing/selftests/sysfs/sysfs.sh | 1376 +++++++++++++++++
13 files changed, 2648 insertions(+), 1 deletion(-)
create mode 100644 fs/kernfs/failure-injection.c
create mode 100644 lib/test_sysfs.c
create mode 100644 tools/testing/selftests/sysfs/Makefile
create mode 100644 tools/testing/selftests/sysfs/config
create mode 100755 tools/testing/selftests/sysfs/sysfs.sh
--
2.27.0
Here is the fix for both 32=>64 and 64=>32 bit translators and a
selftest that reproduced the issue.
Big thanks to YueHaibing for fuzzing and reporting the issue,
I really appreciate it!
Cc: "David S. Miller" <davem(a)davemloft.net>
Cc: Herbert Xu <herbert(a)gondor.apana.org.au>
Cc: Jakub Kicinski <kuba(a)kernel.org>
Cc: Steffen Klassert <steffen.klassert(a)secunet.com>
Cc: YueHaibing <yuehaibing(a)huawei.com>
Cc: netdev(a)vger.kernel.org
Dmitry Safonov (2):
net/xfrm/compat: Copy xfrm_spdattr_type_t atributes
selftests/net/ipsec: Add test for xfrm_spdattr_type_t
net/xfrm/xfrm_compat.c | 49 ++++++++-
tools/testing/selftests/net/ipsec.c | 165 +++++++++++++++++++++++++++-
2 files changed, 207 insertions(+), 7 deletions(-)
base-commit: e73f0f0ee7541171d89f2e2491130c7771ba58d3
--
2.32.0
Hi,
This patch converts existing UUID runtime test to use KUnit framework.
Below, there's a comparison between the old output format and the new
one. Keep in mind that even if KUnit seems very verbose, this is the
corner case where _every_ test has failed.
* This is how the current output looks like in success:
test_uuid: all 18 tests passed
* And when it fails:
test_uuid: conversion test #1 failed on LE data: 'c33f4995-3701-450e-9fbf-206a2e98e576'
test_uuid: cmp test #2 failed on LE data: 'c33f4995-3701-450e-9fbf-206a2e98e576'
test_uuid: cmp test #2 actual data: 'c33f4995-3701-450e-9fbf-206a2e98e576'
test_uuid: conversion test #3 failed on BE data: 'c33f4995-3701-450e-9fbf-206a2e98e576'
test_uuid: cmp test #4 failed on BE data: 'c33f4995-3701-450e-9fbf-206a2e98e576'
test_uuid: cmp test #4 actual data: 'c33f4995-3701-450e-9fbf-206a2e98e576'
test_uuid: conversion test #5 failed on LE data: '64b4371c-77c1-48f9-8221-29f054fc023b'
test_uuid: cmp test #6 failed on LE data: '64b4371c-77c1-48f9-8221-29f054fc023b'
test_uuid: cmp test #6 actual data: '64b4371c-77c1-48f9-8221-29f054fc023b'
test_uuid: conversion test #7 failed on BE data: '64b4371c-77c1-48f9-8221-29f054fc023b'
test_uuid: cmp test #8 failed on BE data: '64b4371c-77c1-48f9-8221-29f054fc023b'
test_uuid: cmp test #8 actual data: '64b4371c-77c1-48f9-8221-29f054fc023b'
test_uuid: conversion test #9 failed on LE data: '0cb4ddff-a545-4401-9d06-688af53e7f84'
test_uuid: cmp test #10 failed on LE data: '0cb4ddff-a545-4401-9d06-688af53e7f84'
test_uuid: cmp test #10 actual data: '0cb4ddff-a545-4401-9d06-688af53e7f84'
test_uuid: conversion test #11 failed on BE data: '0cb4ddff-a545-4401-9d06-688af53e7f84'
test_uuid: cmp test #12 failed on BE data: '0cb4ddff-a545-4401-9d06-688af53e7f84'
test_uuid: cmp test #12 actual data: '0cb4ddff-a545-4401-9d06-688af53e7f84'
test_uuid: negative test #13 passed on wrong LE data: 'c33f4995-3701-450e-9fbf206a2e98e576 '
test_uuid: negative test #14 passed on wrong BE data: 'c33f4995-3701-450e-9fbf206a2e98e576 '
test_uuid: negative test #15 passed on wrong LE data: '64b4371c-77c1-48f9-8221-29f054XX023b'
test_uuid: negative test #16 passed on wrong BE data: '64b4371c-77c1-48f9-8221-29f054XX023b'
test_uuid: negative test #17 passed on wrong LE data: '0cb4ddff-a545-4401-9d06-688af53e'
test_uuid: negative test #18 passed on wrong BE data: '0cb4ddff-a545-4401-9d06-688af53e'
test_uuid: failed 18 out of 18 tests
* Now, here's how it looks like with KUnit:
======== [PASSED] uuid ========
[PASSED] uuid_correct_be
[PASSED] uuid_correct_le
[PASSED] uuid_wrong_be
[PASSED] uuid_wrong_le
* And if every test fail with KUnit:
======== [FAILED] uuid ========
[FAILED] uuid_correct_be
# uuid_correct_be: ASSERTION FAILED at lib/test_uuid.c:57
Expected uuid_parse(data->uuid, &be) == 1, but
uuid_parse(data->uuid, &be) == 0
failed to parse 'c33f4995-3701-450e-9fbf-206a2e98e576'
# uuid_correct_be: not ok 1 - c33f4995-3701-450e-9fbf-206a2e98e576
# uuid_correct_be: ASSERTION FAILED at lib/test_uuid.c:57
Expected uuid_parse(data->uuid, &be) == 1, but
uuid_parse(data->uuid, &be) == 0
failed to parse '64b4371c-77c1-48f9-8221-29f054fc023b'
# uuid_correct_be: not ok 2 - 64b4371c-77c1-48f9-8221-29f054fc023b
# uuid_correct_be: ASSERTION FAILED at lib/test_uuid.c:57
Expected uuid_parse(data->uuid, &be) == 1, but
uuid_parse(data->uuid, &be) == 0
failed to parse '0cb4ddff-a545-4401-9d06-688af53e7f84'
# uuid_correct_be: not ok 3 - 0cb4ddff-a545-4401-9d06-688af53e7f84
not ok 1 - uuid_correct_be
[FAILED] uuid_correct_le
# uuid_correct_le: ASSERTION FAILED at lib/test_uuid.c:46
Expected guid_parse(data->uuid, &le) == 1, but
guid_parse(data->uuid, &le) == 0
failed to parse 'c33f4995-3701-450e-9fbf-206a2e98e576'
# uuid_correct_le: not ok 1 - c33f4995-3701-450e-9fbf-206a2e98e576
# uuid_correct_le: ASSERTION FAILED at lib/test_uuid.c:46
Expected guid_parse(data->uuid, &le) == 1, but
guid_parse(data->uuid, &le) == 0
failed to parse '64b4371c-77c1-48f9-8221-29f054fc023b'
# uuid_correct_le: not ok 2 - 64b4371c-77c1-48f9-8221-29f054fc023b
# uuid_correct_le: ASSERTION FAILED at lib/test_uuid.c:46
Expected guid_parse(data->uuid, &le) == 1, but
guid_parse(data->uuid, &le) == 0
failed to parse '0cb4ddff-a545-4401-9d06-688af53e7f84'
# uuid_correct_le: not ok 3 - 0cb4ddff-a545-4401-9d06-688af53e7f84
not ok 2 - uuid_correct_le
[FAILED] uuid_wrong_be
# uuid_wrong_be: ASSERTION FAILED at lib/test_uuid.c:77
Expected uuid_parse(*data, &be) == 0, but
uuid_parse(*data, &be) == -22
parsing of 'c33f4995-3701-450e-9fbf206a2e98e576 ' should've failed
# uuid_wrong_be: not ok 1 - c33f4995-3701-450e-9fbf206a2e98e576
# uuid_wrong_be: ASSERTION FAILED at lib/test_uuid.c:77
Expected uuid_parse(*data, &be) == 0, but
uuid_parse(*data, &be) == -22
parsing of '64b4371c-77c1-48f9-8221-29f054XX023b' should've failed
# uuid_wrong_be: not ok 2 - 64b4371c-77c1-48f9-8221-29f054XX023b
# uuid_wrong_be: ASSERTION FAILED at lib/test_uuid.c:77
Expected uuid_parse(*data, &be) == 0, but
uuid_parse(*data, &be) == -22
parsing of '0cb4ddff-a545-4401-9d06-688af53e' should've failed
# uuid_wrong_be: not ok 3 - 0cb4ddff-a545-4401-9d06-688af53e
not ok 3 - uuid_wrong_be
[FAILED] uuid_wrong_le
# uuid_wrong_le: ASSERTION FAILED at lib/test_uuid.c:68
Expected guid_parse(*data, &le) == 0, but
guid_parse(*data, &le) == -22
parsing of 'c33f4995-3701-450e-9fbf206a2e98e576 ' should've failed
# uuid_wrong_le: not ok 1 - c33f4995-3701-450e-9fbf206a2e98e576
# uuid_wrong_le: ASSERTION FAILED at lib/test_uuid.c:68
Expected guid_parse(*data, &le) == 0, but
guid_parse(*data, &le) == -22
parsing of '64b4371c-77c1-48f9-8221-29f054XX023b' should've failed
# uuid_wrong_le: not ok 2 - 64b4371c-77c1-48f9-8221-29f054XX023b
# uuid_wrong_le: ASSERTION FAILED at lib/test_uuid.c:68
Expected guid_parse(*data, &le) == 0, but
guid_parse(*data, &le) == -22
parsing of '0cb4ddff-a545-4401-9d06-688af53e' should've failed
# uuid_wrong_le: not ok 3 - 0cb4ddff-a545-4401-9d06-688af53e
not ok 4 - uuid_wrong_le
Changes from v4:
- Add reviewed-by
v4: https://lore.kernel.org/lkml/20210621133148.9226-1-andrealmeid@collabora.co…
Changes from v3:
- Drop unnecessary casts and braces.
- Simplify Kconfig entry
v3: https://lore.kernel.org/lkml/20210610163959.71634-1-andrealmeid@collabora.c…
Changes from v2:
- Clarify in commit message the new test cases setup
v2: https://lore.kernel.org/lkml/20210609233730.164082-1-andrealmeid@collabora.…
Changes from v1:
- Test suite name: uuid_test -> uuid
- Config name: TEST_UUID -> UUID_KUNIT_TEST
- Config entry in the Kconfig file left where it is
- Converted tests to use _MSG variant
v1: https://lore.kernel.org/lkml/20210605215215.171165-1-andrealmeid@collabora.…
André Almeida (1):
lib: Convert UUID runtime test to KUnit
lib/Kconfig.debug | 8 ++-
lib/Makefile | 2 +-
lib/test_uuid.c | 137 +++++++++++++++++++---------------------------
3 files changed, 64 insertions(+), 83 deletions(-)
--
2.32.0