From 4617721c502b2ddaa4e324e86da4997edf738fa5 Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Wed, 2 Sep 2026 09:55:01 -0400 Subject: ftrace: Synchronize the initialization of ftrace_ops There's some internal state that ftrace_ops needs to have set, but since it can be declared outside of the ftrace.c code, it calls ftrace_ops_init() on the ops in every global function. The issue is that if two tasks call it on the same ops at the same time it is possible to have the initialization of one corrupt the initialization of the other call. Create a ops_mutex to use to synchronize every initialization of the ftrace_ops. The mutex is taken within checking the ftrace_ops flag that states it was initializied but the flag is checked again after the mutex has been taken. Checking first outside the mutex allows it to shortcut having to take the mutex. But then the check needs to be done again after the mute is taken in case of races. Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20260902095501.6b59af20@gandalf.local.home Fixes: f04f24fb7e48d ("ftrace, kprobes: Fix a deadlock on ftrace_regex_lock") Reported-by: sashiko-bot@kernel.org Close: https://lore.kernel.org/all/20260829025528.49A831F000E9@smtp.kernel.org/ Signed-off-by: Steven Rostedt --- .../PCI/endpoint/function/binding/pci-ntb.rst | 38 ++++++++++++++++++++++ .../PCI/endpoint/function/binding/pci-test.rst | 26 +++++++++++++++ 2 files changed, 64 insertions(+) create mode 100644 Documentation/PCI/endpoint/function/binding/pci-ntb.rst create mode 100644 Documentation/PCI/endpoint/function/binding/pci-test.rst (limited to 'Documentation/PCI/endpoint/function') diff --git a/Documentation/PCI/endpoint/function/binding/pci-ntb.rst b/Documentation/PCI/endpoint/function/binding/pci-ntb.rst new file mode 100644 index 000000000..40253d3d5 --- /dev/null +++ b/Documentation/PCI/endpoint/function/binding/pci-ntb.rst @@ -0,0 +1,38 @@ +.. SPDX-License-Identifier: GPL-2.0 + +========================== +PCI NTB Endpoint Function +========================== + +1) Create a subdirectory to pci_epf_ntb directory in configfs. + +Standard EPF Configurable Fields: + +================ =========================================================== +vendorid should be 0x104c +deviceid should be 0xb00d for TI's J721E SoC +revid don't care +progif_code don't care +subclass_code should be 0x00 +baseclass_code should be 0x5 +cache_line_size don't care +subsys_vendor_id don't care +subsys_id don't care +interrupt_pin don't care +msi_interrupts don't care +msix_interrupts don't care +================ =========================================================== + +2) Create a subdirectory to directory created in 1 + +NTB EPF specific configurable fields: + +================ =========================================================== +db_count Number of doorbells; default = 4 +mw1 size of memory window1 +mw2 size of memory window2 +mw3 size of memory window3 +mw4 size of memory window4 +num_mws Number of memory windows; max = 4 +spad_count Number of scratchpad registers; default = 64 +================ =========================================================== diff --git a/Documentation/PCI/endpoint/function/binding/pci-test.rst b/Documentation/PCI/endpoint/function/binding/pci-test.rst new file mode 100644 index 000000000..57ee866fb --- /dev/null +++ b/Documentation/PCI/endpoint/function/binding/pci-test.rst @@ -0,0 +1,26 @@ +.. SPDX-License-Identifier: GPL-2.0 + +========================== +PCI Test Endpoint Function +========================== + +name: Should be "pci_epf_test" to bind to the pci_epf_test driver. + +Configurable Fields: + +================ =========================================================== +vendorid should be 0x104c +deviceid should be 0xb500 for DRA74x and 0xb501 for DRA72x +revid don't care +progif_code don't care +subclass_code don't care +baseclass_code should be 0xff +cache_line_size don't care +subsys_vendor_id don't care +subsys_id don't care +interrupt_pin Should be 1 - INTA, 2 - INTB, 3 - INTC, 4 -INTD +msi_interrupts Should be 1 to 32 depending on the number of MSI interrupts + to test +msix_interrupts Should be 1 to 2048 depending on the number of MSI-X + interrupts to test +================ =========================================================== -- cgit v1.3.1