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Miquel Raynal 6c56e89e4e platform-msi: Free descriptors in platform_msi_domain_free()
commit 81b1e6e6a8 upstream.

Since the addition of platform MSI support, there were two helpers
supposed to allocate/free IRQs for a device:

    platform_msi_domain_alloc_irqs()
    platform_msi_domain_free_irqs()

In these helpers, IRQ descriptors are allocated in the "alloc" routine
while they are freed in the "free" one.

Later, two other helpers have been added to handle IRQ domains on top
of MSI domains:

    platform_msi_domain_alloc()
    platform_msi_domain_free()

Seen from the outside, the logic is pretty close with the former
helpers and people used it with the same logic as before: a
platform_msi_domain_alloc() call should be balanced with a
platform_msi_domain_free() call. While this is probably what was
intended to do, the platform_msi_domain_free() does not remove/free
the IRQ descriptor(s) created/inserted in
platform_msi_domain_alloc().

One effect of such situation is that removing a module that requested
an IRQ will let one orphaned IRQ descriptor (with an allocated MSI
entry) in the device descriptors list. Next time the module will be
inserted back, one will observe that the allocation will happen twice
in the MSI domain, one time for the remaining descriptor, one time for
the new one. It also has the side effect to quickly overshoot the
maximum number of allocated MSI and then prevent any module requesting
an interrupt in the same domain to be inserted anymore.

This situation has been met with loops of insertion/removal of the
mvpp2.ko module (requesting 15 MSIs each time).

Fixes: 552c494a76 ("platform-msi: Allow creation of a MSI-based stacked irq domain")
Cc: stable@vger.kernel.org
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-09 17:38:42 +01:00
arch KVM: nVMX: Free the VMREAD/VMWRITE bitmaps if alloc_kvm_area() fails 2019-01-09 17:38:41 +01:00
block block/bio: Do not zero user pages 2018-12-19 19:19:50 +01:00
certs export.h: remove VMLINUX_SYMBOL() and VMLINUX_SYMBOL_STR() 2018-08-22 23:21:44 +09:00
crypto crypto: do not free algorithm before using 2018-12-13 09:16:21 +01:00
Documentation x86/speculation/l1tf: Drop the swap storage limit restriction when l1tf=off 2019-01-09 17:38:41 +01:00
drivers platform-msi: Free descriptors in platform_msi_domain_free() 2019-01-09 17:38:42 +01:00
firmware kbuild: remove all dummy assignments to obj- 2017-11-18 11:46:06 +09:00
fs proc/sysctl: don't return ENOMEM on lookup when a table is unregistering 2018-12-29 13:37:59 +01:00
include platform-msi: Free descriptors in platform_msi_domain_free() 2019-01-09 17:38:42 +01:00
init sched/pelt: Fix warning and clean up IRQ PELT config 2018-12-19 19:19:49 +01:00
ipc ipc/shm.c: use ERR_CAST() for shm_lock() error return 2018-10-05 16:32:04 -07:00
kernel panic: avoid deadlocks in re-entrant console drivers 2018-12-29 13:37:57 +01:00
lib debugobjects: avoid recursive calls with kmemleak 2018-12-17 09:24:41 +01:00
LICENSES LICENSES: Remove CC-BY-SA-4.0 license text 2018-10-18 11:28:50 +02:00
mm mm: don't miss the last page because of round-off error 2018-12-29 13:37:59 +01:00
net ipv6: route: Fix return value of ip6_neigh_lookup() on neigh_create() error 2019-01-09 17:38:35 +01:00
samples samples: disable CONFIG_SAMPLES for UML 2018-10-11 02:15:46 +09:00
scripts scripts/spdxcheck.py: always open files in binary mode 2018-12-19 19:19:50 +01:00
security selinux: add support for RTM_NEWCHAIN, RTM_DELCHAIN, and RTM_GETCHAIN 2018-12-08 12:59:08 +01:00
sound ASoC: intel: cht_bsw_max98090_ti: Add pmc_plt_clk_0 quirk for Chromebook Gnawty 2019-01-09 17:38:41 +01:00
tools tools/testing/nvdimm: Align test resources to 128M 2018-12-21 14:15:23 +01:00
usr initramfs: move gen_initramfs_list.sh from scripts/ to usr/ 2018-08-22 23:21:44 +09:00
virt KVM: arm64: Fix caching of host MDCR_EL2 value 2018-11-13 11:08:47 -08:00
.clang-format clang-format: Set IndentWrappedFunctionNames false 2018-08-01 18:38:51 +02:00
.cocciconfig
.get_maintainer.ignore
.gitattributes .gitattributes: set git diff driver for C source code files 2016-10-07 18:46:30 -07:00
.gitignore Kbuild updates for v4.17 (2nd) 2018-04-15 17:21:30 -07:00
.mailmap libnvdimm-for-4.19_misc 2018-08-25 18:13:10 -07:00
COPYING COPYING: use the new text with points to the license files 2018-03-23 12:41:45 -06:00
CREDITS 9p: remove Ron Minnich from MAINTAINERS 2018-08-17 16:20:26 -07:00
Kbuild Kbuild updates for v4.15 2017-11-17 17:45:29 -08:00
Kconfig kconfig: move the "Executable file formats" menu to fs/Kconfig.binfmt 2018-08-02 08:06:55 +09:00
MAINTAINERS MAINTAINERS: Add Sasha as a stable branch maintainer 2018-12-01 09:37:25 +01:00
Makefile Linux 4.19.13 2018-12-29 13:37:59 +01:00
README Docs: Added a pointer to the formatted docs to README 2018-03-21 09:02:53 -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.
See Documentation/00-INDEX for a list of what is contained in each file.

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.