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Mathias Nyman f5af638f06 xhci: Fix transfer ring expansion size calculation
The amount of new TRBs needed is calculated incorrectly when expanding a
transfer ring.

The room_on_ring() helper will correctly report that the ring needs
expansion if the enqueue pointer is about to reach the dequeue segment.
If enqueue reaches the dequeue segment then there is no easy way
to expand the ring by adding new segments between enqueue and dequeue.

This leads to ring expansion even if num_trbs_free is larger than
num_trbs we are queueing.

As a result we try to store a negative number in a unsigned int, leading
to a huge percieved trb need, and doubling of ring size.

Rework and rename the room_on_ring() to a helper that checks if ring
needs expansion, and return number of new segments needed. Don't rely on
the tracked ring->num_trbs_free value as turns out it has been unreliable.
Use ring enqueue and dequeue positions to determine expansion need.

The unsigned int issue was first reported first Chao zeng, and a bit
later seen in a real world bug.

Reported-by: chao zeng <chao.zengup@gmail.com>
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=217242
Tested-by: Miller Hunter <MillerH@hearthnhome.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Message-ID: <20230602144009.1225632-7-mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-13 11:34:50 +02:00
arch ARM: 2023-06-04 07:16:53 -04:00
block block: fix revalidate performance regression 2023-05-29 08:40:32 -06:00
certs KEYS: Add missing function documentation 2023-04-24 16:15:52 +03:00
crypto This push fixes the following problems: 2023-05-07 10:57:14 -07:00
Documentation Merge 6.4-rc5 into usb-next 2023-06-05 07:39:02 +02:00
drivers xhci: Fix transfer ring expansion size calculation 2023-06-13 11:34:50 +02:00
fs Fix an ext4 regression which landed during the 6.4 merge window. 2023-06-02 17:25:22 -04:00
include Merge 6.4-rc5 into usb-next 2023-06-05 07:39:02 +02:00
init Objtool changes for v6.4: 2023-04-28 14:02:54 -07:00
io_uring io_uring: undeprecate epoll_ctl support 2023-05-26 20:22:41 -06:00
ipc Merge branch 'work.namespace' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2023-02-24 19:20:07 -08:00
kernel Probes fixes for 6.4-rc4: 2023-06-03 08:23:16 -04:00
lib test_firmware: fix the memory leak of the allocated firmware buffer 2023-05-31 20:31:07 +01:00
LICENSES LICENSES: Add the copyleft-next-0.3.1 license 2022-11-08 15:44:01 +01:00
mm mm: page_table_check: Ensure user pages are not slab pages 2023-05-29 16:14:28 +01:00
net nfsd-6.4 fixes: 2023-06-02 13:38:55 -04:00
rust Rust changes for v6.4 2023-04-30 11:20:22 -07:00
samples samples/bpf: Drop unnecessary fallthrough 2023-05-16 19:44:05 +02:00
scripts Locking changes in v6.4: 2023-05-05 12:56:55 -07:00
security selinux: don't use make's grouped targets feature yet 2023-06-01 13:56:13 -04:00
sound ALSA: hda/realtek: Enable headset onLenovo M70/M90 2023-05-24 14:18:59 +02:00
tools Merge 6.4-rc5 into usb-next 2023-06-05 07:39:02 +02:00
usr initramfs: Check negative timestamp to prevent broken cpio archive 2023-04-16 17:37:01 +09:00
virt KVM: Fix vcpu_array[0] races 2023-05-19 13:56:26 -04:00
.clang-format cxl for v6.4 2023-04-30 11:51:51 -07:00
.cocciconfig
.get_maintainer.ignore get_maintainer: add Alan to .get_maintainer.ignore 2022-08-20 15:17:44 -07:00
.gitattributes .gitattributes: use 'dts' diff driver for *.dtso files 2023-02-26 15:28:23 +09:00
.gitignore linux-kselftest-kunit-6.4-rc1 2023-04-24 12:31:32 -07:00
.mailmap mailmap: add entries for Nikolay Aleksandrov 2023-05-17 09:35:05 +01:00
.rustfmt.toml rust: add .rustfmt.toml 2022-09-28 09:02:20 +02:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS MAINTAINERS: sctp: move Neil to CREDITS 2023-05-12 08:51:32 +01:00
Kbuild Kbuild updates for v6.1 2022-10-10 12:00:45 -07:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS Merge 6.4-rc5 into usb-next 2023-06-05 07:39:02 +02:00
Makefile Linux 6.4-rc5 2023-06-04 14:04:27 -04:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.