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lib: add reference counting tracking infrastructure It can be hard to track where references are taken and released. In networking, we have annoying issues at device or netns dismantles, and we had various proposals to ease root causing them. This patch adds new infrastructure pairing refcount increases and decreases. This will self document code, because programmers will have to associate increments/decrements. This is controled by CONFIG_REF_TRACKER which can be selected by users of this feature. This adds both cpu and memory costs, and thus should probably be used with care. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-04 20:21:55 -08:00
lib/ref_tracker: improve printing stats In case the library is tracking busy subsystem, simply printing stack for every active reference will spam log with long, hard to read, redundant stack traces. To improve readabilty following changes have been made: - reports are printed per stack_handle - log is more compact, - added display name for ref_tracker_dir - it will differentiate multiple subsystems, - stack trace is printed indented, in the same printk call, - info about dropped references is printed as well. Signed-off-by: Andrzej Hajda <andrzej.hajda@intel.com> Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-02 12:21:34 +02:00
lib: add reference counting tracking infrastructure It can be hard to track where references are taken and released. In networking, we have annoying issues at device or netns dismantles, and we had various proposals to ease root causing them. This patch adds new infrastructure pairing refcount increases and decreases. This will self document code, because programmers will have to associate increments/decrements. This is controled by CONFIG_REF_TRACKER which can be selected by users of this feature. This adds both cpu and memory costs, and thus should probably be used with care. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-04 20:21:55 -08:00
lib/ref_tracker: improve printing stats In case the library is tracking busy subsystem, simply printing stack for every active reference will spam log with long, hard to read, redundant stack traces. To improve readabilty following changes have been made: - reports are printed per stack_handle - log is more compact, - added display name for ref_tracker_dir - it will differentiate multiple subsystems, - stack trace is printed indented, in the same printk call, - info about dropped references is printed as well. Signed-off-by: Andrzej Hajda <andrzej.hajda@intel.com> Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-02 12:21:34 +02:00
lib: add reference counting tracking infrastructure It can be hard to track where references are taken and released. In networking, we have annoying issues at device or netns dismantles, and we had various proposals to ease root causing them. This patch adds new infrastructure pairing refcount increases and decreases. This will self document code, because programmers will have to associate increments/decrements. This is controled by CONFIG_REF_TRACKER which can be selected by users of this feature. This adds both cpu and memory costs, and thus should probably be used with care. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-04 20:21:55 -08:00
ref_tracker: allow pr_ostream() to print directly to a seq_file Allow pr_ostream to also output directly to a seq_file without an intermediate buffer. The first caller of +ref_tracker_dir_seq_print() will come in a later patch, so mark that __maybe_unused for now. That designation will be removed once it is used. Reviewed-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20250618-reftrack-dbgfs-v15-5-24fc37ead144@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-18 10:24:18 -04:00
lib: add reference counting tracking infrastructure It can be hard to track where references are taken and released. In networking, we have annoying issues at device or netns dismantles, and we had various proposals to ease root causing them. This patch adds new infrastructure pairing refcount increases and decreases. This will self document code, because programmers will have to associate increments/decrements. This is controled by CONFIG_REF_TRACKER which can be selected by users of this feature. This adds both cpu and memory costs, and thus should probably be used with care. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-04 20:21:55 -08:00
lib/ref_tracker: improve printing stats In case the library is tracking busy subsystem, simply printing stack for every active reference will spam log with long, hard to read, redundant stack traces. To improve readabilty following changes have been made: - reports are printed per stack_handle - log is more compact, - added display name for ref_tracker_dir - it will differentiate multiple subsystems, - stack trace is printed indented, in the same printk call, - info about dropped references is printed as well. Signed-off-by: Andrzej Hajda <andrzej.hajda@intel.com> Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-02 12:21:34 +02:00
lib: add reference counting tracking infrastructure It can be hard to track where references are taken and released. In networking, we have annoying issues at device or netns dismantles, and we had various proposals to ease root causing them. This patch adds new infrastructure pairing refcount increases and decreases. This will self document code, because programmers will have to associate increments/decrements. This is controled by CONFIG_REF_TRACKER which can be selected by users of this feature. This adds both cpu and memory costs, and thus should probably be used with care. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-04 20:21:55 -08:00
lib/ref_tracker: improve printing stats In case the library is tracking busy subsystem, simply printing stack for every active reference will spam log with long, hard to read, redundant stack traces. To improve readabilty following changes have been made: - reports are printed per stack_handle - log is more compact, - added display name for ref_tracker_dir - it will differentiate multiple subsystems, - stack trace is printed indented, in the same printk call, - info about dropped references is printed as well. Signed-off-by: Andrzej Hajda <andrzej.hajda@intel.com> Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-02 12:21:34 +02:00
ref_tracker: automatically register a file in debugfs for a ref_tracker_dir Currently, there is no convenient way to see the info that the ref_tracking infrastructure collects. Attempt to create a file in debugfs when called from ref_tracker_dir_init(). The file is given the name "class@%px", as having the unmodified address is helpful for debugging. This should be safe since this directory is only accessible by root While ref_tracker_dir_init() is generally called from a context where sleeping is OK, ref_tracker_dir_exit() can be called from anywhere. Thus, dentry cleanup must be handled asynchronously. Add a new global xarray that has entries with the ref_tracker_dir pointer as the index and the corresponding debugfs dentry pointer as the value. Instead of removing the debugfs dentry, have ref_tracker_dir_exit() set a mark on the xarray entry and schedule a workqueue job. The workqueue job then walks the xarray looking for marked entries, and removes their xarray entries and the debugfs dentries. Because of this, the debugfs dentry can outlive the corresponding ref_tracker_dir. Have ref_tracker_debugfs_show() take extra care to ensure that it's safe to dereference the dir pointer before using it. Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20250618-reftrack-dbgfs-v15-6-24fc37ead144@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-18 10:24:19 -04:00
ref_tracker: add a way to create a symlink to the ref_tracker_dir debugfs file Add the ability for a subsystem to add a user-friendly symlink that points to a ref_tracker_dir's debugfs file. Add a separate debugfs_symlinks xarray and use that to track symlinks. The reaper workqueue job will remove symlinks before their corresponding dentries. Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20250618-reftrack-dbgfs-v15-7-24fc37ead144@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-18 10:24:20 -04:00
ref_tracker: automatically register a file in debugfs for a ref_tracker_dir Currently, there is no convenient way to see the info that the ref_tracking infrastructure collects. Attempt to create a file in debugfs when called from ref_tracker_dir_init(). The file is given the name "class@%px", as having the unmodified address is helpful for debugging. This should be safe since this directory is only accessible by root While ref_tracker_dir_init() is generally called from a context where sleeping is OK, ref_tracker_dir_exit() can be called from anywhere. Thus, dentry cleanup must be handled asynchronously. Add a new global xarray that has entries with the ref_tracker_dir pointer as the index and the corresponding debugfs dentry pointer as the value. Instead of removing the debugfs dentry, have ref_tracker_dir_exit() set a mark on the xarray entry and schedule a workqueue job. The workqueue job then walks the xarray looking for marked entries, and removes their xarray entries and the debugfs dentries. Because of this, the debugfs dentry can outlive the corresponding ref_tracker_dir. Have ref_tracker_debugfs_show() take extra care to ensure that it's safe to dereference the dir pointer before using it. Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20250618-reftrack-dbgfs-v15-6-24fc37ead144@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-18 10:24:19 -04:00
ref_tracker: add a way to create a symlink to the ref_tracker_dir debugfs file Add the ability for a subsystem to add a user-friendly symlink that points to a ref_tracker_dir's debugfs file. Add a separate debugfs_symlinks xarray and use that to track symlinks. The reaper workqueue job will remove symlinks before their corresponding dentries. Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20250618-reftrack-dbgfs-v15-7-24fc37ead144@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-18 10:24:20 -04:00
ref_tracker: automatically register a file in debugfs for a ref_tracker_dir Currently, there is no convenient way to see the info that the ref_tracking infrastructure collects. Attempt to create a file in debugfs when called from ref_tracker_dir_init(). The file is given the name "class@%px", as having the unmodified address is helpful for debugging. This should be safe since this directory is only accessible by root While ref_tracker_dir_init() is generally called from a context where sleeping is OK, ref_tracker_dir_exit() can be called from anywhere. Thus, dentry cleanup must be handled asynchronously. Add a new global xarray that has entries with the ref_tracker_dir pointer as the index and the corresponding debugfs dentry pointer as the value. Instead of removing the debugfs dentry, have ref_tracker_dir_exit() set a mark on the xarray entry and schedule a workqueue job. The workqueue job then walks the xarray looking for marked entries, and removes their xarray entries and the debugfs dentries. Because of this, the debugfs dentry can outlive the corresponding ref_tracker_dir. Have ref_tracker_debugfs_show() take extra care to ensure that it's safe to dereference the dir pointer before using it. Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20250618-reftrack-dbgfs-v15-6-24fc37ead144@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-18 10:24:19 -04:00
lib/ref_tracker: improve printing stats In case the library is tracking busy subsystem, simply printing stack for every active reference will spam log with long, hard to read, redundant stack traces. To improve readabilty following changes have been made: - reports are printed per stack_handle - log is more compact, - added display name for ref_tracker_dir - it will differentiate multiple subsystems, - stack trace is printed indented, in the same printk call, - info about dropped references is printed as well. Signed-off-by: Andrzej Hajda <andrzej.hajda@intel.com> Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-02 12:21:34 +02:00
treewide: Replace kmalloc with kmalloc_obj for non-scalar types This is the result of running the Coccinelle script from scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to avoid scalar types (which need careful case-by-case checking), and instead replace kmalloc-family calls that allocate struct or union object instances: Single allocations: kmalloc(sizeof(TYPE), ...) are replaced with: kmalloc_obj(TYPE, ...) Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...) are replaced with: kmalloc_objs(TYPE, COUNT, ...) Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...) are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...) (where TYPE may also be *VAR) The resulting allocations no longer return "void *", instead returning "TYPE *". Signed-off-by: Kees Cook <kees@kernel.org>
2026-02-20 23:49:23 -08:00
lib/ref_tracker: improve printing stats In case the library is tracking busy subsystem, simply printing stack for every active reference will spam log with long, hard to read, redundant stack traces. To improve readabilty following changes have been made: - reports are printed per stack_handle - log is more compact, - added display name for ref_tracker_dir - it will differentiate multiple subsystems, - stack trace is printed indented, in the same printk call, - info about dropped references is printed as well. Signed-off-by: Andrzej Hajda <andrzej.hajda@intel.com> Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-02 12:21:34 +02:00
lib/ref_tracker: add printing to memory buffer Similar to stack_(depot|trace)_snprint the patch adds helper to printing stats to memory buffer. It will be helpful in case of debugfs. Signed-off-by: Andrzej Hajda <andrzej.hajda@intel.com> Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-02 12:21:35 +02:00
ref_tracker: have callers pass output function to pr_ostream() In a later patch, we'll be adding a 3rd mechanism for outputting ref_tracker info via seq_file. Instead of a conditional, have the caller set a pointer to an output function in struct ostream. As part of this, the log prefix must be explicitly passed in, as it's too late for the pr_fmt macro. Reviewed-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20250618-reftrack-dbgfs-v15-3-24fc37ead144@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-18 10:24:16 -04:00
lib/ref_tracker: add printing to memory buffer Similar to stack_(depot|trace)_snprint the patch adds helper to printing stats to memory buffer. It will be helpful in case of debugfs. Signed-off-by: Andrzej Hajda <andrzej.hajda@intel.com> Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-02 12:21:35 +02:00
ref_tracker: allow pr_ostream() to print directly to a seq_file Allow pr_ostream to also output directly to a seq_file without an intermediate buffer. The first caller of +ref_tracker_dir_seq_print() will come in a later patch, so mark that __maybe_unused for now. That designation will be removed once it is used. Reviewed-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20250618-reftrack-dbgfs-v15-5-24fc37ead144@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-18 10:24:18 -04:00
lib/ref_tracker: add printing to memory buffer Similar to stack_(depot|trace)_snprint the patch adds helper to printing stats to memory buffer. It will be helpful in case of debugfs. Signed-off-by: Andrzej Hajda <andrzej.hajda@intel.com> Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-02 12:21:35 +02:00
ref_tracker: have callers pass output function to pr_ostream() In a later patch, we'll be adding a 3rd mechanism for outputting ref_tracker info via seq_file. Instead of a conditional, have the caller set a pointer to an output function in struct ostream. As part of this, the log prefix must be explicitly passed in, as it's too late for the pr_fmt macro. Reviewed-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20250618-reftrack-dbgfs-v15-3-24fc37ead144@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-18 10:24:16 -04:00
lib/ref_tracker: add printing to memory buffer Similar to stack_(depot|trace)_snprint the patch adds helper to printing stats to memory buffer. It will be helpful in case of debugfs. Signed-off-by: Andrzej Hajda <andrzej.hajda@intel.com> Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-02 12:21:35 +02:00
ref_tracker: have callers pass output function to pr_ostream() In a later patch, we'll be adding a 3rd mechanism for outputting ref_tracker info via seq_file. Instead of a conditional, have the caller set a pointer to an output function in struct ostream. As part of this, the log prefix must be explicitly passed in, as it's too late for the pr_fmt macro. Reviewed-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20250618-reftrack-dbgfs-v15-3-24fc37ead144@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-18 10:24:16 -04:00
lib/ref_tracker: add printing to memory buffer Similar to stack_(depot|trace)_snprint the patch adds helper to printing stats to memory buffer. It will be helpful in case of debugfs. Signed-off-by: Andrzej Hajda <andrzej.hajda@intel.com> Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-02 12:21:35 +02:00
lib/ref_tracker: add unlocked leak print helper To have reliable detection of leaks, caller must be able to check under the same lock both: tracked counter and the leaks. dir.lock is natural candidate for such lock and unlocked print helper can be called with this lock taken. As a bonus we can reuse this helper in ref_tracker_dir_exit. Signed-off-by: Andrzej Hajda <andrzej.hajda@intel.com> Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-02 12:21:33 +02:00
lib/ref_tracker: improve printing stats In case the library is tracking busy subsystem, simply printing stack for every active reference will spam log with long, hard to read, redundant stack traces. To improve readabilty following changes have been made: - reports are printed per stack_handle - log is more compact, - added display name for ref_tracker_dir - it will differentiate multiple subsystems, - stack trace is printed indented, in the same printk call, - info about dropped references is printed as well. Signed-off-by: Andrzej Hajda <andrzej.hajda@intel.com> Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-02 12:21:34 +02:00
lib/ref_tracker: add unlocked leak print helper To have reliable detection of leaks, caller must be able to check under the same lock both: tracked counter and the leaks. dir.lock is natural candidate for such lock and unlocked print helper can be called with this lock taken. As a bonus we can reuse this helper in ref_tracker_dir_exit. Signed-off-by: Andrzej Hajda <andrzej.hajda@intel.com> Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-02 12:21:33 +02:00
lib/ref_tracker: improve printing stats In case the library is tracking busy subsystem, simply printing stack for every active reference will spam log with long, hard to read, redundant stack traces. To improve readabilty following changes have been made: - reports are printed per stack_handle - log is more compact, - added display name for ref_tracker_dir - it will differentiate multiple subsystems, - stack trace is printed indented, in the same printk call, - info about dropped references is printed as well. Signed-off-by: Andrzej Hajda <andrzej.hajda@intel.com> Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-02 12:21:34 +02:00
ref_tracker: have callers pass output function to pr_ostream() In a later patch, we'll be adding a 3rd mechanism for outputting ref_tracker info via seq_file. Instead of a conditional, have the caller set a pointer to an output function in struct ostream. As part of this, the log prefix must be explicitly passed in, as it's too late for the pr_fmt macro. Reviewed-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20250618-reftrack-dbgfs-v15-3-24fc37ead144@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-18 10:24:16 -04:00
ref_tracker: eliminate the ref_tracker_dir name field Now that we have dentries and the ability to create meaningful symlinks to them, don't keep a name string in each tracker. Switch the output format to print "class@address", and drop the name field. Also, add a kerneldoc header for ref_tracker_dir_init(). Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20250618-reftrack-dbgfs-v15-9-24fc37ead144@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-18 10:24:22 -04:00
lib/ref_tracker: improve printing stats In case the library is tracking busy subsystem, simply printing stack for every active reference will spam log with long, hard to read, redundant stack traces. To improve readabilty following changes have been made: - reports are printed per stack_handle - log is more compact, - added display name for ref_tracker_dir - it will differentiate multiple subsystems, - stack trace is printed indented, in the same printk call, - info about dropped references is printed as well. Signed-off-by: Andrzej Hajda <andrzej.hajda@intel.com> Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-02 12:21:34 +02:00
lib/ref_tracker: add unlocked leak print helper To have reliable detection of leaks, caller must be able to check under the same lock both: tracked counter and the leaks. dir.lock is natural candidate for such lock and unlocked print helper can be called with this lock taken. As a bonus we can reuse this helper in ref_tracker_dir_exit. Signed-off-by: Andrzej Hajda <andrzej.hajda@intel.com> Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-02 12:21:33 +02:00
lib/ref_tracker: improve printing stats In case the library is tracking busy subsystem, simply printing stack for every active reference will spam log with long, hard to read, redundant stack traces. To improve readabilty following changes have been made: - reports are printed per stack_handle - log is more compact, - added display name for ref_tracker_dir - it will differentiate multiple subsystems, - stack trace is printed indented, in the same printk call, - info about dropped references is printed as well. Signed-off-by: Andrzej Hajda <andrzej.hajda@intel.com> Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-02 12:21:34 +02:00
ref_tracker: remove redundant __GFP_NOWARN Commit 16f5dfbc851b ("gfp: include __GFP_NOWARN in GFP_NOWAIT") made GFP_NOWAIT implicitly include __GFP_NOWARN. Therefore, explicit __GFP_NOWARN combined with GFP_NOWAIT (e.g., `GFP_NOWAIT | __GFP_NOWARN`) is now redundant. Let's clean up these redundant flags across subsystems. No functional changes. Link: https://lkml.kernel.org/r/20250805023031.331718-1-rongqianfeng@vivo.com Signed-off-by: Qianfeng Rong <rongqianfeng@vivo.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-08-05 10:30:31 +08:00
lib/ref_tracker: improve printing stats In case the library is tracking busy subsystem, simply printing stack for every active reference will spam log with long, hard to read, redundant stack traces. To improve readabilty following changes have been made: - reports are printed per stack_handle - log is more compact, - added display name for ref_tracker_dir - it will differentiate multiple subsystems, - stack trace is printed indented, in the same printk call, - info about dropped references is printed as well. Signed-off-by: Andrzej Hajda <andrzej.hajda@intel.com> Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-02 12:21:34 +02:00
ref_tracker: have callers pass output function to pr_ostream() In a later patch, we'll be adding a 3rd mechanism for outputting ref_tracker info via seq_file. Instead of a conditional, have the caller set a pointer to an output function in struct ostream. As part of this, the log prefix must be explicitly passed in, as it's too late for the pr_fmt macro. Reviewed-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20250618-reftrack-dbgfs-v15-3-24fc37ead144@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-18 10:24:16 -04:00
ref_tracker: eliminate the ref_tracker_dir name field Now that we have dentries and the ability to create meaningful symlinks to them, don't keep a name string in each tracker. Switch the output format to print "class@address", and drop the name field. Also, add a kerneldoc header for ref_tracker_dir_init(). Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20250618-reftrack-dbgfs-v15-9-24fc37ead144@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-18 10:24:22 -04:00
ref_tracker: have callers pass output function to pr_ostream() In a later patch, we'll be adding a 3rd mechanism for outputting ref_tracker info via seq_file. Instead of a conditional, have the caller set a pointer to an output function in struct ostream. As part of this, the log prefix must be explicitly passed in, as it's too late for the pr_fmt macro. Reviewed-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20250618-reftrack-dbgfs-v15-3-24fc37ead144@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-18 10:24:16 -04:00
lib/ref_tracker: improve printing stats In case the library is tracking busy subsystem, simply printing stack for every active reference will spam log with long, hard to read, redundant stack traces. To improve readabilty following changes have been made: - reports are printed per stack_handle - log is more compact, - added display name for ref_tracker_dir - it will differentiate multiple subsystems, - stack trace is printed indented, in the same printk call, - info about dropped references is printed as well. Signed-off-by: Andrzej Hajda <andrzej.hajda@intel.com> Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-02 12:21:34 +02:00
ref_tracker: have callers pass output function to pr_ostream() In a later patch, we'll be adding a 3rd mechanism for outputting ref_tracker info via seq_file. Instead of a conditional, have the caller set a pointer to an output function in struct ostream. As part of this, the log prefix must be explicitly passed in, as it's too late for the pr_fmt macro. Reviewed-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20250618-reftrack-dbgfs-v15-3-24fc37ead144@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-18 10:24:16 -04:00
ref_tracker: eliminate the ref_tracker_dir name field Now that we have dentries and the ability to create meaningful symlinks to them, don't keep a name string in each tracker. Switch the output format to print "class@address", and drop the name field. Also, add a kerneldoc header for ref_tracker_dir_init(). Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20250618-reftrack-dbgfs-v15-9-24fc37ead144@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-18 10:24:22 -04:00
lib/ref_tracker: improve printing stats In case the library is tracking busy subsystem, simply printing stack for every active reference will spam log with long, hard to read, redundant stack traces. To improve readabilty following changes have been made: - reports are printed per stack_handle - log is more compact, - added display name for ref_tracker_dir - it will differentiate multiple subsystems, - stack trace is printed indented, in the same printk call, - info about dropped references is printed as well. Signed-off-by: Andrzej Hajda <andrzej.hajda@intel.com> Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-02 12:21:34 +02:00
lib/ref_tracker: add unlocked leak print helper To have reliable detection of leaks, caller must be able to check under the same lock both: tracked counter and the leaks. dir.lock is natural candidate for such lock and unlocked print helper can be called with this lock taken. As a bonus we can reuse this helper in ref_tracker_dir_exit. Signed-off-by: Andrzej Hajda <andrzej.hajda@intel.com> Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-02 12:21:33 +02:00
lib/ref_tracker: add printing to memory buffer Similar to stack_(depot|trace)_snprint the patch adds helper to printing stats to memory buffer. It will be helpful in case of debugfs. Signed-off-by: Andrzej Hajda <andrzej.hajda@intel.com> Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-02 12:21:35 +02:00
ref_tracker: have callers pass output function to pr_ostream() In a later patch, we'll be adding a 3rd mechanism for outputting ref_tracker info via seq_file. Instead of a conditional, have the caller set a pointer to an output function in struct ostream. As part of this, the log prefix must be explicitly passed in, as it's too late for the pr_fmt macro. Reviewed-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20250618-reftrack-dbgfs-v15-3-24fc37ead144@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-18 10:24:16 -04:00
lib/ref_tracker: add printing to memory buffer Similar to stack_(depot|trace)_snprint the patch adds helper to printing stats to memory buffer. It will be helpful in case of debugfs. Signed-off-by: Andrzej Hajda <andrzej.hajda@intel.com> Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-02 12:21:35 +02:00
lib/ref_tracker: add unlocked leak print helper To have reliable detection of leaks, caller must be able to check under the same lock both: tracked counter and the leaks. dir.lock is natural candidate for such lock and unlocked print helper can be called with this lock taken. As a bonus we can reuse this helper in ref_tracker_dir_exit. Signed-off-by: Andrzej Hajda <andrzej.hajda@intel.com> Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-02 12:21:33 +02:00
lib/ref_tracker: add printing to memory buffer Similar to stack_(depot|trace)_snprint the patch adds helper to printing stats to memory buffer. It will be helpful in case of debugfs. Signed-off-by: Andrzej Hajda <andrzej.hajda@intel.com> Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-02 12:21:35 +02:00
ref_tracker: have callers pass output function to pr_ostream() In a later patch, we'll be adding a 3rd mechanism for outputting ref_tracker info via seq_file. Instead of a conditional, have the caller set a pointer to an output function in struct ostream. As part of this, the log prefix must be explicitly passed in, as it's too late for the pr_fmt macro. Reviewed-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20250618-reftrack-dbgfs-v15-3-24fc37ead144@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-18 10:24:16 -04:00
lib/ref_tracker: add printing to memory buffer Similar to stack_(depot|trace)_snprint the patch adds helper to printing stats to memory buffer. It will be helpful in case of debugfs. Signed-off-by: Andrzej Hajda <andrzej.hajda@intel.com> Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-02 12:21:35 +02:00
lib: add reference counting tracking infrastructure It can be hard to track where references are taken and released. In networking, we have annoying issues at device or netns dismantles, and we had various proposals to ease root causing them. This patch adds new infrastructure pairing refcount increases and decreases. This will self document code, because programmers will have to associate increments/decrements. This is controled by CONFIG_REF_TRACKER which can be selected by users of this feature. This adds both cpu and memory costs, and thus should probably be used with care. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-04 20:21:55 -08:00
ref_tracker: implement use-after-free detection Whenever ref_tracker_dir_init() is called, mark the struct ref_tracker_dir as dead. Test the dead status from ref_tracker_alloc() and ref_tracker_free() This should detect buggy dev_put()/dev_hold() happening too late in netdevice dismantle process. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-04 14:42:35 -08:00
ref_tracker: automatically register a file in debugfs for a ref_tracker_dir Currently, there is no convenient way to see the info that the ref_tracking infrastructure collects. Attempt to create a file in debugfs when called from ref_tracker_dir_init(). The file is given the name "class@%px", as having the unmodified address is helpful for debugging. This should be safe since this directory is only accessible by root While ref_tracker_dir_init() is generally called from a context where sleeping is OK, ref_tracker_dir_exit() can be called from anywhere. Thus, dentry cleanup must be handled asynchronously. Add a new global xarray that has entries with the ref_tracker_dir pointer as the index and the corresponding debugfs dentry pointer as the value. Instead of removing the debugfs dentry, have ref_tracker_dir_exit() set a mark on the xarray entry and schedule a workqueue job. The workqueue job then walks the xarray looking for marked entries, and removes their xarray entries and the debugfs dentries. Because of this, the debugfs dentry can outlive the corresponding ref_tracker_dir. Have ref_tracker_debugfs_show() take extra care to ensure that it's safe to dereference the dir pointer before using it. Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20250618-reftrack-dbgfs-v15-6-24fc37ead144@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-18 10:24:19 -04:00
lib: add reference counting tracking infrastructure It can be hard to track where references are taken and released. In networking, we have annoying issues at device or netns dismantles, and we had various proposals to ease root causing them. This patch adds new infrastructure pairing refcount increases and decreases. This will self document code, because programmers will have to associate increments/decrements. This is controled by CONFIG_REF_TRACKER which can be selected by users of this feature. This adds both cpu and memory costs, and thus should probably be used with care. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-04 20:21:55 -08:00
lib/ref_tracker: add unlocked leak print helper To have reliable detection of leaks, caller must be able to check under the same lock both: tracked counter and the leaks. dir.lock is natural candidate for such lock and unlocked print helper can be called with this lock taken. As a bonus we can reuse this helper in ref_tracker_dir_exit. Signed-off-by: Andrzej Hajda <andrzej.hajda@intel.com> Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-02 12:21:33 +02:00
lib: add reference counting tracking infrastructure It can be hard to track where references are taken and released. In networking, we have annoying issues at device or netns dismantles, and we had various proposals to ease root causing them. This patch adds new infrastructure pairing refcount increases and decreases. This will self document code, because programmers will have to associate increments/decrements. This is controled by CONFIG_REF_TRACKER which can be selected by users of this feature. This adds both cpu and memory costs, and thus should probably be used with care. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-04 20:21:55 -08:00
lib/ref_tracker: add unlocked leak print helper To have reliable detection of leaks, caller must be able to check under the same lock both: tracked counter and the leaks. dir.lock is natural candidate for such lock and unlocked print helper can be called with this lock taken. As a bonus we can reuse this helper in ref_tracker_dir_exit. Signed-off-by: Andrzej Hajda <andrzej.hajda@intel.com> Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-02 12:21:33 +02:00
lib: add reference counting tracking infrastructure It can be hard to track where references are taken and released. In networking, we have annoying issues at device or netns dismantles, and we had various proposals to ease root causing them. This patch adds new infrastructure pairing refcount increases and decreases. This will self document code, because programmers will have to associate increments/decrements. This is controled by CONFIG_REF_TRACKER which can be selected by users of this feature. This adds both cpu and memory costs, and thus should probably be used with care. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-04 20:21:55 -08:00
ref_tracker: add a count of untracked references We are still chasing a netdev refcount imbalance, and we suspect we have one rogue dev_put() that is consuming a reference taken from a dev_hold_track() To detect this case, allow ref_tracker_alloc() and ref_tracker_free() to be called with a NULL @trackerp parameter, and use a dedicated refcount_t just for them. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-04 14:42:36 -08:00
lib: add reference counting tracking infrastructure It can be hard to track where references are taken and released. In networking, we have annoying issues at device or netns dismantles, and we had various proposals to ease root causing them. This patch adds new infrastructure pairing refcount increases and decreases. This will self document code, because programmers will have to associate increments/decrements. This is controled by CONFIG_REF_TRACKER which can be selected by users of this feature. This adds both cpu and memory costs, and thus should probably be used with care. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-04 20:21:55 -08:00
lib/ref_tracker: remove warnings in case of allocation failure Library can handle allocation failures. To avoid allocation warnings __GFP_NOWARN has been added everywhere. Moreover GFP_ATOMIC has been replaced with GFP_NOWAIT in case of stack allocation on tracker free call. Signed-off-by: Andrzej Hajda <andrzej.hajda@intel.com> Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-02 12:21:36 +02:00
lib: add reference counting tracking infrastructure It can be hard to track where references are taken and released. In networking, we have annoying issues at device or netns dismantles, and we had various proposals to ease root causing them. This patch adds new infrastructure pairing refcount increases and decreases. This will self document code, because programmers will have to associate increments/decrements. This is controled by CONFIG_REF_TRACKER which can be selected by users of this feature. This adds both cpu and memory costs, and thus should probably be used with care. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-04 20:21:55 -08:00
ref_tracker: implement use-after-free detection Whenever ref_tracker_dir_init() is called, mark the struct ref_tracker_dir as dead. Test the dead status from ref_tracker_alloc() and ref_tracker_free() This should detect buggy dev_put()/dev_hold() happening too late in netdevice dismantle process. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-04 14:42:35 -08:00
ref_tracker: add a count of untracked references We are still chasing a netdev refcount imbalance, and we suspect we have one rogue dev_put() that is consuming a reference taken from a dev_hold_track() To detect this case, allow ref_tracker_alloc() and ref_tracker_free() to be called with a NULL @trackerp parameter, and use a dedicated refcount_t just for them. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-04 14:42:36 -08:00
ref_tracker: use __GFP_NOFAIL more carefully syzbot was able to trigger this warning from new_slab() /* * All existing users of the __GFP_NOFAIL are blockable, so warn * of any new users that actually require GFP_NOWAIT */ if (WARN_ON_ONCE(!can_direct_reclaim)) goto fail; Indeed, we should use __GFP_NOFAIL if direct reclaim is possible. Hopefully in the future we will be able to use SLAB_NOFAILSLAB option so that syzbot can benefit from full ref_tracker even in the presence of memory fault injections. WARNING: CPU: 0 PID: 13 at mm/page_alloc.c:5081 __alloc_pages_slowpath.constprop.0+0x1b7b/0x20d0 mm/page_alloc.c:5081 mm/page_alloc.c:5081 Modules linked in: CPU: 0 PID: 13 Comm: ksoftirqd/0 Not tainted 5.16.0-rc5-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__alloc_pages_slowpath.constprop.0+0x1b7b/0x20d0 mm/page_alloc.c:5081 mm/page_alloc.c:5081 Code: 90 08 00 00 48 81 c7 d8 04 00 00 48 89 f8 48 c1 e8 03 42 80 3c 30 00 0f 84 f0 ea ff ff e8 3d 82 09 00 e9 e6 ea ff ff 4d 89 fd <0f> 0b 48 b8 00 00 00 00 00 fc ff df 48 8b 54 24 30 48 c1 ea 03 80 RSP: 0018:ffffc90000d272b8 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffff88813fffc300 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000002 RDI: ffff88813fffc348 RBP: ffff88813fffc300 R08: 00000000000013dc R09: 00000000000013c8 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: ffffc90000d274e8 R14: dffffc0000000000 R15: ffffc90000d274e8 FS: 0000000000000000(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffefe6000f8 CR3: 000000001d21e000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> __alloc_pages+0x412/0x500 mm/page_alloc.c:5382 mm/page_alloc.c:5382 alloc_pages+0x1a7/0x300 mm/mempolicy.c:2191 mm/mempolicy.c:2191 alloc_slab_page mm/slub.c:1793 [inline] allocate_slab mm/slub.c:1938 [inline] alloc_slab_page mm/slub.c:1793 [inline] mm/slub.c:1993 allocate_slab mm/slub.c:1938 [inline] mm/slub.c:1993 new_slab+0x349/0x4a0 mm/slub.c:1993 mm/slub.c:1993 ___slab_alloc+0x918/0xfe0 mm/slub.c:3022 mm/slub.c:3022 __slab_alloc.constprop.0+0x4d/0xa0 mm/slub.c:3109 mm/slub.c:3109 slab_alloc_node mm/slub.c:3200 [inline] slab_alloc mm/slub.c:3242 [inline] slab_alloc_node mm/slub.c:3200 [inline] mm/slub.c:3259 slab_alloc mm/slub.c:3242 [inline] mm/slub.c:3259 kmem_cache_alloc_trace+0x289/0x2c0 mm/slub.c:3259 mm/slub.c:3259 kmalloc include/linux/slab.h:590 [inline] kzalloc include/linux/slab.h:724 [inline] kmalloc include/linux/slab.h:590 [inline] lib/ref_tracker.c:74 kzalloc include/linux/slab.h:724 [inline] lib/ref_tracker.c:74 ref_tracker_alloc+0xe1/0x430 lib/ref_tracker.c:74 lib/ref_tracker.c:74 netdev_tracker_alloc include/linux/netdevice.h:3855 [inline] dev_hold_track include/linux/netdevice.h:3872 [inline] netdev_tracker_alloc include/linux/netdevice.h:3855 [inline] net/core/dst.c:52 dev_hold_track include/linux/netdevice.h:3872 [inline] net/core/dst.c:52 dst_init+0xe0/0x520 net/core/dst.c:52 net/core/dst.c:52 dst_alloc+0x16b/0x1f0 net/core/dst.c:96 net/core/dst.c:96 rt_dst_alloc+0x73/0x450 net/ipv4/route.c:1614 net/ipv4/route.c:1614 ip_route_input_mc net/ipv4/route.c:1720 [inline] ip_route_input_mc net/ipv4/route.c:1720 [inline] net/ipv4/route.c:2465 ip_route_input_rcu.part.0+0x4fe/0xcc0 net/ipv4/route.c:2465 net/ipv4/route.c:2465 ip_route_input_rcu net/ipv4/route.c:2420 [inline] ip_route_input_rcu net/ipv4/route.c:2420 [inline] net/ipv4/route.c:2416 ip_route_input_noref+0x1b8/0x2a0 net/ipv4/route.c:2416 net/ipv4/route.c:2416 ip_rcv_finish_core.constprop.0+0x288/0x1e90 net/ipv4/ip_input.c:354 net/ipv4/ip_input.c:354 ip_rcv_finish+0x135/0x2f0 net/ipv4/ip_input.c:427 net/ipv4/ip_input.c:427 NF_HOOK include/linux/netfilter.h:307 [inline] NF_HOOK include/linux/netfilter.h:301 [inline] NF_HOOK include/linux/netfilter.h:307 [inline] net/ipv4/ip_input.c:540 NF_HOOK include/linux/netfilter.h:301 [inline] net/ipv4/ip_input.c:540 ip_rcv+0xaa/0xd0 net/ipv4/ip_input.c:540 net/ipv4/ip_input.c:540 __netif_receive_skb_one_core+0x114/0x180 net/core/dev.c:5350 net/core/dev.c:5350 __netif_receive_skb+0x24/0x1b0 net/core/dev.c:5464 net/core/dev.c:5464 process_backlog+0x2a5/0x6c0 net/core/dev.c:5796 net/core/dev.c:5796 __napi_poll+0xaf/0x440 net/core/dev.c:6364 net/core/dev.c:6364 napi_poll net/core/dev.c:6431 [inline] napi_poll net/core/dev.c:6431 [inline] net/core/dev.c:6518 net_rx_action+0x801/0xb40 net/core/dev.c:6518 net/core/dev.c:6518 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558 kernel/softirq.c:558 run_ksoftirqd kernel/softirq.c:921 [inline] run_ksoftirqd kernel/softirq.c:921 [inline] kernel/softirq.c:913 run_ksoftirqd+0x2d/0x60 kernel/softirq.c:913 kernel/softirq.c:913 smpboot_thread_fn+0x645/0x9c0 kernel/smpboot.c:164 kernel/smpboot.c:164 kthread+0x405/0x4f0 kernel/kthread.c:327 kernel/kthread.c:327 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 arch/x86/entry/entry_64.S:295 Fixes: 4e66934eaadc ("lib: add reference counting tracking infrastructure") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Dmitry Vyukov <dvyukov@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-01-12 03:14:45 -08:00
treewide: Replace kmalloc with kmalloc_obj for non-scalar types This is the result of running the Coccinelle script from scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to avoid scalar types (which need careful case-by-case checking), and instead replace kmalloc-family calls that allocate struct or union object instances: Single allocations: kmalloc(sizeof(TYPE), ...) are replaced with: kmalloc_obj(TYPE, ...) Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...) are replaced with: kmalloc_objs(TYPE, COUNT, ...) Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...) are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...) (where TYPE may also be *VAR) The resulting allocations no longer return "void *", instead returning "TYPE *". Signed-off-by: Kees Cook <kees@kernel.org>
2026-02-20 23:49:23 -08:00
lib: add reference counting tracking infrastructure It can be hard to track where references are taken and released. In networking, we have annoying issues at device or netns dismantles, and we had various proposals to ease root causing them. This patch adds new infrastructure pairing refcount increases and decreases. This will self document code, because programmers will have to associate increments/decrements. This is controled by CONFIG_REF_TRACKER which can be selected by users of this feature. This adds both cpu and memory costs, and thus should probably be used with care. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-04 20:21:55 -08:00
ref_tracker: add a count of untracked references We are still chasing a netdev refcount imbalance, and we suspect we have one rogue dev_put() that is consuming a reference taken from a dev_hold_track() To detect this case, allow ref_tracker_alloc() and ref_tracker_free() to be called with a NULL @trackerp parameter, and use a dedicated refcount_t just for them. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-04 14:42:36 -08:00
lib: add reference counting tracking infrastructure It can be hard to track where references are taken and released. In networking, we have annoying issues at device or netns dismantles, and we had various proposals to ease root causing them. This patch adds new infrastructure pairing refcount increases and decreases. This will self document code, because programmers will have to associate increments/decrements. This is controled by CONFIG_REF_TRACKER which can be selected by users of this feature. This adds both cpu and memory costs, and thus should probably be used with care. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-04 20:21:55 -08:00
ref_tracker: implement use-after-free detection Whenever ref_tracker_dir_init() is called, mark the struct ref_tracker_dir as dead. Test the dead status from ref_tracker_alloc() and ref_tracker_free() This should detect buggy dev_put()/dev_hold() happening too late in netdevice dismantle process. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-04 14:42:35 -08:00
ref_tracker: add a count of untracked references We are still chasing a netdev refcount imbalance, and we suspect we have one rogue dev_put() that is consuming a reference taken from a dev_hold_track() To detect this case, allow ref_tracker_alloc() and ref_tracker_free() to be called with a NULL @trackerp parameter, and use a dedicated refcount_t just for them. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-04 14:42:36 -08:00
lib: add reference counting tracking infrastructure It can be hard to track where references are taken and released. In networking, we have annoying issues at device or netns dismantles, and we had various proposals to ease root causing them. This patch adds new infrastructure pairing refcount increases and decreases. This will self document code, because programmers will have to associate increments/decrements. This is controled by CONFIG_REF_TRACKER which can be selected by users of this feature. This adds both cpu and memory costs, and thus should probably be used with care. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-04 20:21:55 -08:00
lib/ref_tracker: remove warnings in case of allocation failure Library can handle allocation failures. To avoid allocation warnings __GFP_NOWARN has been added everywhere. Moreover GFP_ATOMIC has been replaced with GFP_NOWAIT in case of stack allocation on tracker free call. Signed-off-by: Andrzej Hajda <andrzej.hajda@intel.com> Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-02 12:21:36 +02:00
ref_tracker: remove redundant __GFP_NOWARN Commit 16f5dfbc851b ("gfp: include __GFP_NOWARN in GFP_NOWAIT") made GFP_NOWAIT implicitly include __GFP_NOWARN. Therefore, explicit __GFP_NOWARN combined with GFP_NOWAIT (e.g., `GFP_NOWAIT | __GFP_NOWARN`) is now redundant. Let's clean up these redundant flags across subsystems. No functional changes. Link: https://lkml.kernel.org/r/20250805023031.331718-1-rongqianfeng@vivo.com Signed-off-by: Qianfeng Rong <rongqianfeng@vivo.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-08-05 10:30:31 +08:00
lib: add reference counting tracking infrastructure It can be hard to track where references are taken and released. In networking, we have annoying issues at device or netns dismantles, and we had various proposals to ease root causing them. This patch adds new infrastructure pairing refcount increases and decreases. This will self document code, because programmers will have to associate increments/decrements. This is controled by CONFIG_REF_TRACKER which can be selected by users of this feature. This adds both cpu and memory costs, and thus should probably be used with care. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-04 20:21:55 -08:00
ref_tracker: add a top level debugfs directory for ref_tracker Add a new "ref_tracker" directory in debugfs. Each individual refcount tracker can register files under there to display info about currently-held references. Reviewed-by: Andrew Lunn <andrew@lunn.ch> Reviewed-by: Krzysztof Karas <krzysztof.karas@intel.com> Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20250618-reftrack-dbgfs-v15-2-24fc37ead144@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-18 10:24:15 -04:00
ref_tracker: allow pr_ostream() to print directly to a seq_file Allow pr_ostream to also output directly to a seq_file without an intermediate buffer. The first caller of +ref_tracker_dir_seq_print() will come in a later patch, so mark that __maybe_unused for now. That designation will be removed once it is used. Reviewed-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20250618-reftrack-dbgfs-v15-5-24fc37ead144@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-18 10:24:18 -04:00
ref_tracker: automatically register a file in debugfs for a ref_tracker_dir Currently, there is no convenient way to see the info that the ref_tracking infrastructure collects. Attempt to create a file in debugfs when called from ref_tracker_dir_init(). The file is given the name "class@%px", as having the unmodified address is helpful for debugging. This should be safe since this directory is only accessible by root While ref_tracker_dir_init() is generally called from a context where sleeping is OK, ref_tracker_dir_exit() can be called from anywhere. Thus, dentry cleanup must be handled asynchronously. Add a new global xarray that has entries with the ref_tracker_dir pointer as the index and the corresponding debugfs dentry pointer as the value. Instead of removing the debugfs dentry, have ref_tracker_dir_exit() set a mark on the xarray entry and schedule a workqueue job. The workqueue job then walks the xarray looking for marked entries, and removes their xarray entries and the debugfs dentries. Because of this, the debugfs dentry can outlive the corresponding ref_tracker_dir. Have ref_tracker_debugfs_show() take extra care to ensure that it's safe to dereference the dir pointer before using it. Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20250618-reftrack-dbgfs-v15-6-24fc37ead144@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-18 10:24:19 -04:00
ref_tracker: allow pr_ostream() to print directly to a seq_file Allow pr_ostream to also output directly to a seq_file without an intermediate buffer. The first caller of +ref_tracker_dir_seq_print() will come in a later patch, so mark that __maybe_unused for now. That designation will be removed once it is used. Reviewed-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20250618-reftrack-dbgfs-v15-5-24fc37ead144@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-18 10:24:18 -04:00
ref_tracker: automatically register a file in debugfs for a ref_tracker_dir Currently, there is no convenient way to see the info that the ref_tracking infrastructure collects. Attempt to create a file in debugfs when called from ref_tracker_dir_init(). The file is given the name "class@%px", as having the unmodified address is helpful for debugging. This should be safe since this directory is only accessible by root While ref_tracker_dir_init() is generally called from a context where sleeping is OK, ref_tracker_dir_exit() can be called from anywhere. Thus, dentry cleanup must be handled asynchronously. Add a new global xarray that has entries with the ref_tracker_dir pointer as the index and the corresponding debugfs dentry pointer as the value. Instead of removing the debugfs dentry, have ref_tracker_dir_exit() set a mark on the xarray entry and schedule a workqueue job. The workqueue job then walks the xarray looking for marked entries, and removes their xarray entries and the debugfs dentries. Because of this, the debugfs dentry can outlive the corresponding ref_tracker_dir. Have ref_tracker_debugfs_show() take extra care to ensure that it's safe to dereference the dir pointer before using it. Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20250618-reftrack-dbgfs-v15-6-24fc37ead144@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-18 10:24:19 -04:00
ref_tracker: use %p instead of %px in debugfs dentry name As Kees points out, this is a kernel address leak, and debugging is not a sufficiently good reason to expose the real kernel address. Fixes: 65b584f53611 ("ref_tracker: automatically register a file in debugfs for a ref_tracker_dir") Reported-by: Kees Cook <kees@kernel.org> Closes: https://lore.kernel.org/netdev/202507301603.62E553F93@keescook/ Signed-off-by: Jeff Layton <jlayton@kernel.org> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-08-08 07:45:23 -04:00
ref_tracker: automatically register a file in debugfs for a ref_tracker_dir Currently, there is no convenient way to see the info that the ref_tracking infrastructure collects. Attempt to create a file in debugfs when called from ref_tracker_dir_init(). The file is given the name "class@%px", as having the unmodified address is helpful for debugging. This should be safe since this directory is only accessible by root While ref_tracker_dir_init() is generally called from a context where sleeping is OK, ref_tracker_dir_exit() can be called from anywhere. Thus, dentry cleanup must be handled asynchronously. Add a new global xarray that has entries with the ref_tracker_dir pointer as the index and the corresponding debugfs dentry pointer as the value. Instead of removing the debugfs dentry, have ref_tracker_dir_exit() set a mark on the xarray entry and schedule a workqueue job. The workqueue job then walks the xarray looking for marked entries, and removes their xarray entries and the debugfs dentries. Because of this, the debugfs dentry can outlive the corresponding ref_tracker_dir. Have ref_tracker_debugfs_show() take extra care to ensure that it's safe to dereference the dir pointer before using it. Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20250618-reftrack-dbgfs-v15-6-24fc37ead144@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-18 10:24:19 -04:00
ref_tracker: add a way to create a symlink to the ref_tracker_dir debugfs file Add the ability for a subsystem to add a user-friendly symlink that points to a ref_tracker_dir's debugfs file. Add a separate debugfs_symlinks xarray and use that to track symlinks. The reaper workqueue job will remove symlinks before their corresponding dentries. Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20250618-reftrack-dbgfs-v15-7-24fc37ead144@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-18 10:24:20 -04:00
ref_tracker: automatically register a file in debugfs for a ref_tracker_dir Currently, there is no convenient way to see the info that the ref_tracking infrastructure collects. Attempt to create a file in debugfs when called from ref_tracker_dir_init(). The file is given the name "class@%px", as having the unmodified address is helpful for debugging. This should be safe since this directory is only accessible by root While ref_tracker_dir_init() is generally called from a context where sleeping is OK, ref_tracker_dir_exit() can be called from anywhere. Thus, dentry cleanup must be handled asynchronously. Add a new global xarray that has entries with the ref_tracker_dir pointer as the index and the corresponding debugfs dentry pointer as the value. Instead of removing the debugfs dentry, have ref_tracker_dir_exit() set a mark on the xarray entry and schedule a workqueue job. The workqueue job then walks the xarray looking for marked entries, and removes their xarray entries and the debugfs dentries. Because of this, the debugfs dentry can outlive the corresponding ref_tracker_dir. Have ref_tracker_debugfs_show() take extra care to ensure that it's safe to dereference the dir pointer before using it. Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20250618-reftrack-dbgfs-v15-6-24fc37ead144@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-18 10:24:19 -04:00
ref_tracker: add a way to create a symlink to the ref_tracker_dir debugfs file Add the ability for a subsystem to add a user-friendly symlink that points to a ref_tracker_dir's debugfs file. Add a separate debugfs_symlinks xarray and use that to track symlinks. The reaper workqueue job will remove symlinks before their corresponding dentries. Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20250618-reftrack-dbgfs-v15-7-24fc37ead144@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-18 10:24:20 -04:00
ref_tracker: automatically register a file in debugfs for a ref_tracker_dir Currently, there is no convenient way to see the info that the ref_tracking infrastructure collects. Attempt to create a file in debugfs when called from ref_tracker_dir_init(). The file is given the name "class@%px", as having the unmodified address is helpful for debugging. This should be safe since this directory is only accessible by root While ref_tracker_dir_init() is generally called from a context where sleeping is OK, ref_tracker_dir_exit() can be called from anywhere. Thus, dentry cleanup must be handled asynchronously. Add a new global xarray that has entries with the ref_tracker_dir pointer as the index and the corresponding debugfs dentry pointer as the value. Instead of removing the debugfs dentry, have ref_tracker_dir_exit() set a mark on the xarray entry and schedule a workqueue job. The workqueue job then walks the xarray looking for marked entries, and removes their xarray entries and the debugfs dentries. Because of this, the debugfs dentry can outlive the corresponding ref_tracker_dir. Have ref_tracker_debugfs_show() take extra care to ensure that it's safe to dereference the dir pointer before using it. Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20250618-reftrack-dbgfs-v15-6-24fc37ead144@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-18 10:24:19 -04:00
ref_tracker: do xarray and workqueue job initializations earlier The kernel test robot reported an oops that occurred when attempting to deregister a dentry from the xarray during subsys_initcall(). The ref_tracker xarrays and workqueue job are being initialized in late_initcall() which is too late. Move those to postcore_initcall() instead. Fixes: 65b584f53611 ("ref_tracker: automatically register a file in debugfs for a ref_tracker_dir") Reported-by: kernel test robot <oliver.sang@intel.com> Closes: https://lore.kernel.org/oe-lkp/202506251406.c28f2adb-lkp@intel.com Signed-off-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org> Link: https://patch.msgid.link/20250626-reftrack-dbgfs-v1-1-812102e2a394@kernel.org
2025-06-26 08:52:14 -04:00
ref_tracker: add a top level debugfs directory for ref_tracker Add a new "ref_tracker" directory in debugfs. Each individual refcount tracker can register files under there to display info about currently-held references. Reviewed-by: Andrew Lunn <andrew@lunn.ch> Reviewed-by: Krzysztof Karas <krzysztof.karas@intel.com> Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20250618-reftrack-dbgfs-v15-2-24fc37ead144@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-18 10:24:15 -04:00
ref_tracker: automatically register a file in debugfs for a ref_tracker_dir Currently, there is no convenient way to see the info that the ref_tracking infrastructure collects. Attempt to create a file in debugfs when called from ref_tracker_dir_init(). The file is given the name "class@%px", as having the unmodified address is helpful for debugging. This should be safe since this directory is only accessible by root While ref_tracker_dir_init() is generally called from a context where sleeping is OK, ref_tracker_dir_exit() can be called from anywhere. Thus, dentry cleanup must be handled asynchronously. Add a new global xarray that has entries with the ref_tracker_dir pointer as the index and the corresponding debugfs dentry pointer as the value. Instead of removing the debugfs dentry, have ref_tracker_dir_exit() set a mark on the xarray entry and schedule a workqueue job. The workqueue job then walks the xarray looking for marked entries, and removes their xarray entries and the debugfs dentries. Because of this, the debugfs dentry can outlive the corresponding ref_tracker_dir. Have ref_tracker_debugfs_show() take extra care to ensure that it's safe to dereference the dir pointer before using it. Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20250618-reftrack-dbgfs-v15-6-24fc37ead144@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-18 10:24:19 -04:00
ref_tracker: add a way to create a symlink to the ref_tracker_dir debugfs file Add the ability for a subsystem to add a user-friendly symlink that points to a ref_tracker_dir's debugfs file. Add a separate debugfs_symlinks xarray and use that to track symlinks. The reaper workqueue job will remove symlinks before their corresponding dentries. Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20250618-reftrack-dbgfs-v15-7-24fc37ead144@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-18 10:24:20 -04:00
ref_tracker: do xarray and workqueue job initializations earlier The kernel test robot reported an oops that occurred when attempting to deregister a dentry from the xarray during subsys_initcall(). The ref_tracker xarrays and workqueue job are being initialized in late_initcall() which is too late. Move those to postcore_initcall() instead. Fixes: 65b584f53611 ("ref_tracker: automatically register a file in debugfs for a ref_tracker_dir") Reported-by: kernel test robot <oliver.sang@intel.com> Closes: https://lore.kernel.org/oe-lkp/202506251406.c28f2adb-lkp@intel.com Signed-off-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org> Link: https://patch.msgid.link/20250626-reftrack-dbgfs-v1-1-812102e2a394@kernel.org
2025-06-26 08:52:14 -04:00
ref_tracker: add a top level debugfs directory for ref_tracker Add a new "ref_tracker" directory in debugfs. Each individual refcount tracker can register files under there to display info about currently-held references. Reviewed-by: Andrew Lunn <andrew@lunn.ch> Reviewed-by: Krzysztof Karas <krzysztof.karas@intel.com> Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20250618-reftrack-dbgfs-v15-2-24fc37ead144@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-18 10:24:15 -04:00
ref_tracker: do xarray and workqueue job initializations earlier The kernel test robot reported an oops that occurred when attempting to deregister a dentry from the xarray during subsys_initcall(). The ref_tracker xarrays and workqueue job are being initialized in late_initcall() which is too late. Move those to postcore_initcall() instead. Fixes: 65b584f53611 ("ref_tracker: automatically register a file in debugfs for a ref_tracker_dir") Reported-by: kernel test robot <oliver.sang@intel.com> Closes: https://lore.kernel.org/oe-lkp/202506251406.c28f2adb-lkp@intel.com Signed-off-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org> Link: https://patch.msgid.link/20250626-reftrack-dbgfs-v1-1-812102e2a394@kernel.org
2025-06-26 08:52:14 -04:00
ref_tracker: add a top level debugfs directory for ref_tracker Add a new "ref_tracker" directory in debugfs. Each individual refcount tracker can register files under there to display info about currently-held references. Reviewed-by: Andrew Lunn <andrew@lunn.ch> Reviewed-by: Krzysztof Karas <krzysztof.karas@intel.com> Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://patch.msgid.link/20250618-reftrack-dbgfs-v15-2-24fc37ead144@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-18 10:24:15 -04:00