kernel/linux.git/drivers/thunderbolt/debugfs.c, branch v7.2-rc1

thunderbolt: debugfs: Fix sideband write size check

2026-06-08T10:47:28+00:00

sb_regs_write() looks up the matching sideband register entry before validating the number of bytes to write. However, the size check uses sb_regs->size, which is the size of the first entry in the register table, instead of the matched entry. This rejects valid writes to larger sideband registers such as USB4_SB_DEBUG or USB4_SB_DATA. Use the matched register entry for the size check. Signed-off-by: Xu Rao Signed-off-by: Mika Westerberg

thunderbolt: debugfs: Fix margining error counter buffer leak

2026-06-04T04:58:59+00:00

When USB4 lane margining debugfs write support is enabled, margining_error_counter_write() copies the user input with validate_and_copy_from_user(). This allocates a temporary page that is only needed while parsing the requested error counter mode. The function currently returns without freeing that page. This leaks one page per write to the error_counter debugfs file, including successful writes and writes that later fail while taking the domain lock or because software margining is not enabled. Free the temporary page once parsing has completed, and also before returning from the invalid-input path. Fixes: 10904df3f20c ("thunderbolt: Improve software receiver lane margining") Signed-off-by: Xu Rao Signed-off-by: Mika Westerberg

thunderbolt: Remove XDomain from the bus without holding tb->lock

2026-05-05T11:53:46+00:00

Currently we call device_unregister() for services and the XDomain itself with tb->lock held. This prevents the service drivers from calling any functions that may take it. For this reason separate removing the XDomain from the topology data structures (where we need the lock) from unregistering the device from the bus (where remove callbacks of the drivers are being called). Signed-off-by: Mika Westerberg

thunderbolt: debugfs: Don't stop reading SB registers if just one fails

2026-04-27T05:12:55+00:00

The GEN4 TxFFE register is not part of the USB4 v1.0 specification, so understandably some pre-USB4v2 retimers (like the Parade PS8830) don't seem to implement it. The immediate idea to counter this would be to introduce a version check for that specific register, but on a second thought, the current flow only returns a quiet -EIO if there's any failures, without hinting at what the actual problem is. To take care of both of these issues, simply print an error line for each SB register read that fails and go on with attempting to read the others. Note that this is not quite in-spec behavior ("The SB Register Space registers shall have the structure and fields described in Table 4-17. Registers not listed in Table 4-20 are undefined and shall not be used."), but it's the easiest fix that shouldn't have real-world bad side effects. Fixes: 6d241fa00159 ("thunderbolt: Add sideband register access to debugfs") Signed-off-by: Konrad Dybcio Signed-off-by: Mika Westerberg

Convert 'alloc_obj' family to use the new default GFP_KERNEL argument

2026-02-22T01:09:51+00:00

This was done entirely with mindless brute force, using git grep -l '\

treewide: Replace kmalloc with kmalloc_obj for non-scalar types

2026-02-21T09:02:28+00:00

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

thunderbolt: Fix typos in debugfs.c

2025-11-17T07:22:51+00:00

Fix typos in debugfs.c. No functional changes. Signed-off-by: Alan Borzeszkowski Signed-off-by: Mika Westerberg

thunderbolt: Use string choices helpers

2025-08-26T05:59:41+00:00

Use string_choices.h helpers instead of hard-coded strings. Signed-off-by: Chelsy Ratnawat Signed-off-by: Mika Westerberg

thunderbolt: Expose router DROM through debugfs

2025-01-05T08:35:03+00:00

Router DROM contains information that might be usable for development and debugging purposes. For example when new entries are added to the USB4 spec it is useful to be able to look for them without need to change the kernel. For this reason expose the DROM through debugfs. Signed-off-by: Mika Westerberg

thunderbolt: debugfs: Add write capability to path config space

2025-01-03T09:50:02+00:00

Currently debugfs interface allows writing of router, adapter and counters config spaces but not for paths. However, it can be useful during debugging to modify path config space so for this reason add this support to the debugfs interface as well. Signed-off-by: Gil Fine Signed-off-by: Mika Westerberg