From 034dd340b08be1f2f0477ad16131d609f9dbd53c Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sun, 30 Aug 2026 09:22:00 -0700 Subject: Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull tracing fixes from Steven Rostedt: - Fix error output of boot instance creation failure Currently if a boot instance creation fails, instead of printing out the name of the instance that failed, it prints "(null)". That is because it prints "cur_str" that had already been processed by strsep(). Print the saved name instead. While at it, print the error code of the failure. - Fix use-after-free for same named historgrams Histograms can be named so that they can be used in multiple events. But if the named histogram has a variable attached, the second event that uses the named histogram which duplicates it and needs to free the original after duplication leaves the old variable in place and still visible. If another histogram uses than variable, it will use the stale one which will try to reference the freed duplicate histogram and crash the kernel. Free the duplicate variables along with the duplicated histogram data. - Check return value of kthread_run() in event self test The events self tests uses a kthread for testing but does not check if it succeeded in creating a kthread. If the kthread creation were to fail, the code will still try to call kthread_stop() on the error returned. - Fix race between reading trace_pipe and updating subbuffer size If a user is reading the trace_pipe file at the same time they update the ring buffer sub-buffer size, can cause the trace_pipe read to read stale data. Add trace_access_lock() around updating the ring buffer sub-buffer size. - Fix eventfs_inode on failure path in creation of the events directory In the creation of the "events" directory, if after allocating the eventfs_inode a failure is detected, it calls cleanup_ei() which calls free_ei(). The free_ei() will test if eventfs_inode being freed has no children. It is a bug if it does. But on the failure case of the creation of the "events" directory, the children lists have not yet been initialized and the free will trigger a warning because list_empty() on an uninitialized list returns false. Move the initialization into init_ei() where it makes more sense and makes sure that a created eventfs_inode has its lists initialized upon creation. - Check return value of kthread_run() in ftrace direct sample code The sample code that shows how to use the ftrace direct calls does not test the return of kthread_run() to see if it succeeds. Return a failure if the kthread_run() doesn't succeed. - Clear user events state on fork in case of alloc failure On fork, the child gets a pointer to the parent's user events state. It makes a copy of it then updates the child's pointer to it. But if the allocation fails, the duplication function leaves the child with a pointer to its parent's descriptor. When the child cleans up its data, it will free the parent's descriptor while the parent is still using it. In the duplication function, set the child's user_event_mm to NULL before testing if the allocation succeeded, and when it exits it will not free the parent's descriptor. - Fix retry exhaustion in simple ring buffer reader swap simple_ring_buffer_swap_reader_page() starts with retry set to 8 and post-decrements it only after a failed link replacement. On the final attempt, a successful replacement leaves retry at zero, while a failed replacement leaves it at -1. But the check for success expects the retry value to be non-zero and exits with an error on zero. This is the opposite result. Fix it. - Fail nicely when the remote swap_reader_page() returns an error Currently, if the swap_reader_page() of a remote buffer fails, it triggers a WARN_ON_ONCE() and continues normally. Instead, have it exit with an error and a pr_warn() print instead of a full WARNING. * tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: ring-buffer: Stop remote reader update when page swap fails tracing: Fix retry exhaustion in simple ring buffer reader swap tracing/user_events: Clear copied tracing state before fork duplication samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify eventfs: Initialize ei->children and ei->list in init_ei() tracing: Fix use-after-free in trace_pipe read on sub-buffer order change tracing: Fix crash passing ERR_PTR to kthread_stop() tracing: Fix use-after-free with same-name named triggers tracing: Fix logged instance name on creation failure --- drivers/thunderbolt/cap.c | 256 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 256 insertions(+) create mode 100644 drivers/thunderbolt/cap.c (limited to 'drivers/thunderbolt/cap.c') diff --git a/drivers/thunderbolt/cap.c b/drivers/thunderbolt/cap.c new file mode 100644 index 000000000..4ab22d529 --- /dev/null +++ b/drivers/thunderbolt/cap.c @@ -0,0 +1,256 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Thunderbolt driver - capabilities lookup + * + * Copyright (c) 2014 Andreas Noever + * Copyright (C) 2018, Intel Corporation + */ + +#include +#include + +#include "tb.h" + +#define CAP_OFFSET_MAX 0xff +#define VSE_CAP_OFFSET_MAX 0xffff +#define TMU_ACCESS_EN BIT(20) + +static int tb_port_enable_tmu(struct tb_port *port, bool enable) +{ + struct tb_switch *sw = port->sw; + u32 value, offset; + int ret; + + /* + * Legacy devices need to have TMU access enabled before port + * space can be fully accessed. + */ + if (tb_switch_is_light_ridge(sw)) + offset = 0x26; + else if (tb_switch_is_eagle_ridge(sw)) + offset = 0x2a; + else + return 0; + + ret = tb_sw_read(sw, &value, TB_CFG_SWITCH, offset, 1); + if (ret) + return ret; + + if (enable) + value |= TMU_ACCESS_EN; + else + value &= ~TMU_ACCESS_EN; + + return tb_sw_write(sw, &value, TB_CFG_SWITCH, offset, 1); +} + +static void tb_port_dummy_read(struct tb_port *port) +{ + /* + * When reading from next capability pointer location in port + * config space the read data is not cleared on LR. To avoid + * reading stale data on next read perform one dummy read after + * port capabilities are walked. + */ + if (tb_switch_is_light_ridge(port->sw)) { + u32 dummy; + + tb_port_read(port, &dummy, TB_CFG_PORT, 0, 1); + } +} + +/** + * tb_port_next_cap() - Return next capability in the linked list + * @port: Port to find the capability for + * @offset: Previous capability offset (%0 for start) + * + * Finds dword offset of the next capability in port config space + * capability list. When passed %0 in @offset parameter, first entry + * will be returned, if it exists. + * + * Return: + * * Double word offset of the first or next capability - On success. + * * %0 - If no next capability is found. + * * Negative errno - Another error occurred. + */ +int tb_port_next_cap(struct tb_port *port, unsigned int offset) +{ + struct tb_cap_any header; + int ret; + + if (!offset) + return port->config.first_cap_offset; + + ret = tb_port_read(port, &header, TB_CFG_PORT, offset, 1); + if (ret) + return ret; + + return header.basic.next; +} + +static int __tb_port_find_cap(struct tb_port *port, enum tb_port_cap cap) +{ + int offset = 0; + + do { + struct tb_cap_any header; + int ret; + + offset = tb_port_next_cap(port, offset); + if (offset < 0) + return offset; + + ret = tb_port_read(port, &header, TB_CFG_PORT, offset, 1); + if (ret) + return ret; + + if (header.basic.cap == cap) + return offset; + } while (offset > 0); + + return -ENOENT; +} + +/** + * tb_port_find_cap() - Find port capability + * @port: Port to find the capability for + * @cap: Capability to look + * + * Return: + * * Offset to the start of capability - On success. + * * %-ENOENT - If no such capability was found. + * * Negative errno - Another error occurred. + */ +int tb_port_find_cap(struct tb_port *port, enum tb_port_cap cap) +{ + int ret; + + ret = tb_port_enable_tmu(port, true); + if (ret) + return ret; + + ret = __tb_port_find_cap(port, cap); + + tb_port_dummy_read(port); + tb_port_enable_tmu(port, false); + + return ret; +} + +/** + * tb_switch_next_cap() - Return next capability in the linked list + * @sw: Switch to find the capability for + * @offset: Previous capability offset (%0 for start) + * + * Finds dword offset of the next capability in port config space + * capability list. When passed %0 in @offset parameter, first entry + * will be returned, if it exists. + * + * Return: + * * Double word offset of the first or next capability - On success. + * * %0 - If no next capability is found. + * * Negative errno - Another error occurred. + */ +int tb_switch_next_cap(struct tb_switch *sw, unsigned int offset) +{ + struct tb_cap_any header; + int ret; + + if (!offset) + return sw->config.first_cap_offset; + + ret = tb_sw_read(sw, &header, TB_CFG_SWITCH, offset, 2); + if (ret) + return ret; + + switch (header.basic.cap) { + case TB_SWITCH_CAP_TMU: + ret = header.basic.next; + break; + + case TB_SWITCH_CAP_VSE: + if (!header.extended_short.length) + ret = header.extended_long.next; + else + ret = header.extended_short.next; + break; + + default: + tb_sw_dbg(sw, "unknown capability %#x at %#x\n", + header.basic.cap, offset); + ret = -EINVAL; + break; + } + + return ret >= VSE_CAP_OFFSET_MAX ? 0 : ret; +} + +/** + * tb_switch_find_cap() - Find switch capability + * @sw: Switch to find the capability for + * @cap: Capability to look + * + * Return: + * * Offset to the start of capability - On success. + * * %-ENOENT - If no such capability was found. + * * Negative errno - Another error occurred. + */ +int tb_switch_find_cap(struct tb_switch *sw, enum tb_switch_cap cap) +{ + int offset = 0; + + do { + struct tb_cap_any header; + int ret; + + offset = tb_switch_next_cap(sw, offset); + if (offset < 0) + return offset; + + ret = tb_sw_read(sw, &header, TB_CFG_SWITCH, offset, 1); + if (ret) + return ret; + + if (header.basic.cap == cap) + return offset; + } while (offset); + + return -ENOENT; +} + +/** + * tb_switch_find_vse_cap() - Find switch vendor specific capability + * @sw: Switch to find the capability for + * @vsec: Vendor specific capability to look + * + * This function enumerates vendor specific capabilities (VSEC) of a + * switch and returns offset when capability matching @vsec is found. + * + * Return: + * * Offset of capability - On success. + * * %-ENOENT - If capability was not found. + * * Negative errno - Another error occurred. + */ +int tb_switch_find_vse_cap(struct tb_switch *sw, enum tb_switch_vse_cap vsec) +{ + int offset = 0; + + do { + struct tb_cap_any header; + int ret; + + offset = tb_switch_next_cap(sw, offset); + if (offset < 0) + return offset; + + ret = tb_sw_read(sw, &header, TB_CFG_SWITCH, offset, 1); + if (ret) + return ret; + + if (header.extended_short.cap == TB_SWITCH_CAP_VSE && + header.extended_short.vsec_id == vsec) + return offset; + } while (offset); + + return -ENOENT; +} -- cgit v1.3.1