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authorNuoqi Gui <gnq25@mails.tsinghua.edu.cn>2026-09-04 12:41:55 +0200
committerAlexei Starovoitov <ast@kernel.org>2026-09-04 12:24:25 -0700
commit2b97956af60810cd382b86b9ce9aea421b889861 (patch)
tree7d9b0d8a91f77e63deff23976f68555a4895346a /Documentation/PCI/controller
downloadlinux-stable-2b97956af60810cd382b86b9ce9aea421b889861.tar.gz
linux-stable-2b97956af60810cd382b86b9ce9aea421b889861.zip
selftests/bpf: Test rhtab kptr cancellation semanticsgrafted
Resizable hash-map updates and deletions must not perform full special-field destruction in their caller context. In particular, a referenced kptr must remain attached to the allocation until the memory allocator destructor can release it safely. Add separate coverage for both affected paths. The update test stores a task kptr, replaces the ordinary value bytes with BPF_EXIST, and verifies that the kptr survived. The delete test removes an element and exchanges its kptr through the still-valid map-value pointer before the allocation is reclaimed. Both cases observe a NULL kptr when rhtab uses bpf_obj_free_fields(). They recover and release the reference after rhtab switches to cancellation semantics. Signed-off-by: Nuoqi Gui <gnq25@mails.tsinghua.edu.cn> [ kkd: Split update and delete coverage and rewrote the commit log ] Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> Link: https://lore.kernel.org/r/20260904104203.345917-5-memxor@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Diffstat (limited to 'Documentation/PCI/controller')
-rw-r--r--Documentation/PCI/controller/index.rst10
-rw-r--r--Documentation/PCI/controller/rcar-pcie-firmware.rst32
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diff --git a/Documentation/PCI/controller/index.rst b/Documentation/PCI/controller/index.rst
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+.. SPDX-License-Identifier: GPL-2.0
+
+===========================================
+PCI Native Host Bridge and Endpoint Drivers
+===========================================
+
+.. toctree::
+ :maxdepth: 2
+
+ rcar-pcie-firmware
diff --git a/Documentation/PCI/controller/rcar-pcie-firmware.rst b/Documentation/PCI/controller/rcar-pcie-firmware.rst
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+.. SPDX-License-Identifier: GPL-2.0
+
+=================================================
+Firmware of PCIe controller for Renesas R-Car V4H
+=================================================
+
+Renesas R-Car V4H (r8a779g0) has a PCIe controller, requiring a specific
+firmware download during startup.
+
+However, Renesas currently cannot distribute the firmware free of charge.
+
+The firmware file "104_PCIe_fw_addr_data_ver1.05.txt" (note that the file name
+might be different between different datasheet revisions) can be found in the
+datasheet encoded as text, and as such, the file's content must be converted
+back to binary form. This can be achieved using the following example script:
+
+.. code-block:: sh
+
+ $ awk '/^\s*0x[0-9A-Fa-f]{4}\s+0x[0-9A-Fa-f]{4}/ { print substr($2,5,2) substr($2,3,2) }' \
+ 104_PCIe_fw_addr_data_ver1.05.txt | \
+ xxd -p -r > rcar_gen4_pcie.bin
+
+Once the text content has been converted into a binary firmware file, verify
+its checksum as follows:
+
+.. code-block:: sh
+
+ $ sha1sum rcar_gen4_pcie.bin
+ 1d0bd4b189b4eb009f5d564b1f93a79112994945 rcar_gen4_pcie.bin
+
+The resulting binary file called "rcar_gen4_pcie.bin" should be placed in the
+"/lib/firmware" directory before the driver runs.