Performance oriented customized Linux kernel based on the mainline kernel.
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Julian Wiedmann f9e50b02a9 s390/qeth: fix dangling IO buffers after halt/clear
The cio layer's intparm logic does not align itself well with how qeth
manages cmd IOs. When an active IO gets terminated via halt/clear, the
corresponding IRQ's intparm does not reflect the cmd buffer but rather
the intparm that was passed to ccw_device_halt() / ccw_device_clear().
This behaviour was recently clarified in
commit b91d9e67e5 ("s390/cio: fix intparm documentation").

As a result, qeth_irq() currently doesn't cancel a cmd that was
terminated via halt/clear. This primarily causes us to leak
card->read_cmd after the qeth device is removed, since our IO path still
holds a refcount for this cmd.

For qeth this means that we need to keep track of which IO is pending on
a device ('active_cmd'), and use this as the intparm when calling
halt/clear. Otherwise qeth_irq() can't match the subsequent IRQ to its
cmd buffer.
Since we now keep track of the _expected_ intparm, we can also detect
any mismatch; this would constitute a bug somewhere in the lower layers.
In this case cancel the active cmd - we effectively "lost" the IRQ and
should not expect any further notification for this IO.

Fixes: 405548959c ("s390/qeth: add support for dynamically allocated cmds")
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-12-05 12:25:05 -08:00
arch Merge branch 'akpm' (patches from Andrew) 2019-12-01 20:36:41 -08:00
block compat_ioctl: remove most of fs/compat_ioctl.c 2019-12-01 13:46:15 -08:00
certs certs: Add wrapper function to check blacklisted binary hash 2019-11-12 12:25:50 +11:00
crypto Merge git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2019-11-25 19:49:58 -08:00
Documentation Merge branch 'akpm' (patches from Andrew) 2019-12-01 20:36:41 -08:00
drivers s390/qeth: fix dangling IO buffers after halt/clear 2019-12-05 12:25:05 -08:00
fs Merge branch 'akpm' (patches from Andrew) 2019-12-01 20:36:41 -08:00
include net: Fixed updating of ethertype in skb_mpls_push() 2019-12-04 17:11:25 -08:00
init Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace 2019-12-01 13:26:18 -08:00
ipc y2038: remove CONFIG_64BIT_TIME 2019-11-15 14:38:27 +01:00
kernel Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf 2019-12-02 10:50:29 -08:00
lib Merge branch 'akpm' (patches from Andrew) 2019-12-01 20:36:41 -08:00
LICENSES LICENSES: Rename other to deprecated 2019-05-03 06:34:32 -06:00
mm mm/page_io.c: annotate refault stalls from swap_readpage 2019-12-01 12:59:11 -08:00
net hsr: fix a NULL pointer dereference in hsr_dev_xmit() 2019-12-05 12:09:02 -08:00
samples New tracing features: 2019-11-27 11:42:01 -08:00
scripts Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf 2019-12-02 10:50:29 -08:00
security y2038: syscall implementation cleanups 2019-12-01 14:00:59 -08:00
sound compat_ioctl: remove most of fs/compat_ioctl.c 2019-12-01 13:46:15 -08:00
tools Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf 2019-12-02 10:50:29 -08:00
usr kbuild: update compile-test header list for v5.4-rc2 2019-10-05 15:29:49 +09:00
virt KVM: Fix jump label out_free_* in kvm_init() 2019-11-23 11:29:17 +01:00
.clang-format clang-format: Update with the latest for_each macro list 2019-08-31 10:00:51 +02:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.get_maintainer.ignore Opt out of scripts/get_maintainer.pl 2019-05-16 10:53:40 -07:00
.gitattributes .gitattributes: set git diff driver for C source code files 2016-10-07 18:46:30 -07:00
.gitignore Modules updates for v5.4 2019-09-22 10:34:46 -07:00
.mailmap Merge branch 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2019-11-26 14:52:11 -08:00
COPYING COPYING: use the new text with points to the license files 2018-03-23 12:41:45 -06:00
CREDITS MAINTAINERS: Remove Simon as Renesas SoC Co-Maintainer 2019-10-10 08:12:51 -07:00
Kbuild kbuild: do not descend to ./Kbuild when cleaning 2019-08-21 21:03:58 +09:00
Kconfig docs: kbuild: convert docs to ReST and rename to *.rst 2019-06-14 14:21:21 -06:00
MAINTAINERS MAINTAINERS: add myself as maintainer of MCAN MMIO device driver 2019-12-03 11:15:08 +01:00
Makefile Linux 5.4 2019-11-24 16:32:01 -08:00
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.