redonkable/alistair23-linux
redonkable/alistair23-linux
1
0
Fork 0
Code Releases Activity
Fork of alistair23 Linux kernel for reMarkable from https://github.com/alistair23/linux
649818 commits 15 branches 0 tags 3.4 GiB
C 97.7%
Assembly 1.4%
Makefile 0.3%
Shell 0.2%
Python 0.1%
Other 0.1%
Go to file
Linus Walleij e13934bdf4 mmc: core/mmci: restore pre/post_req behaviour 
commit 64b12a68a9
"mmc: core: fix prepared requests while doing bkops"
is fixing a bug in the wrong way. A bug in the MMCI
device driver is fixed by amending the MMC core.

Thinking about it: what the pre- and post-callbacks
are doing is to essentially map and unmap SG lists
for DMA transfers. Why would we not be able to do that
just because a BKOPS command is sent inbetween?
Having to unprepare/prepare the next asynchronous
request for DMA seems wrong.

Looking the backtrace in that commit we can see what
the real problem actually is:

mmci_data_irq() is calling mmci_dma_unmap() twice
which is goung to call arm_dma_unmap_sg() twice
and v7_dma_inv_range() twice for the same sglist
and that will crash.

This happens because a request is prepared, then
a BKOPS is sent. The IRQ completing the BKOPS command
goes through mmci_data_irq() and thinks that a DMA
operation has just been completed because
dma_inprogress() reports true. It then proceeds to
unmap the sglist.

But that was wrong! dma_inprogress() should NOT be
true because no DMA was actually in progress! We had
just prepared the sglist, and the DMA channel
dma_current has been configured, but NOT started!

Because of this, the sglist is already unmapped when
we get our actual data completion IRQ, and we are
unmapping the sglist once more, and we get this crash.

Therefore, we need to revert this solution pushing
the problem to the core and causing problems, and
instead augment the implementation such that
dma_inprogress() only reports true if some DMA has
actually been started.

After this we can keep the request prepared during the
BKOPS and we need not unprepare/reprepare it.

Fixes: 64b12a68a9 ("mmc: core: fix prepared requests while doing bkops")
Cc: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2017-02-13 13:20:52 +01:00
arch MIPS: Alchemy: Don't rely on public mmc header to include interrupt.h 2017-02-13 13:20:18 +01:00
block block: don't try Write Same from __blkdev_issue_zeroout 2017-02-06 09:34:46 -07:00
certs certs: Add a secondary system keyring that can be added to dynamically 2016-04-11 22:48:09 +01:00
crypto crypto: algif_aead - Fix kernel panic on list_del 2017-02-03 17:45:48 +08:00
Documentation mmc: dt: Document binding for eMMC DDR 3.3V I/O voltage support 2017-02-13 13:20:45 +01:00
drivers mmc: core/mmci: restore pre/post_req behaviour 2017-02-13 13:20:52 +01:00
firmware
fs Merge branch 'for-linus-4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs 2017-02-11 09:15:58 -08:00
include mmc: core: Invent MMC_CAP_3_3V_DDR 2017-02-13 13:20:44 +01:00
init kbuild: modversions: add infrastructure for emitting relative CRCs 2017-02-03 08:28:25 -08:00
ipc ipc/sem.c: fix incorrect sem_lock pairing 2017-01-10 18:31:55 -08:00
kernel Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-02-11 10:24:16 -08:00
lib mm: do not export ioremap_page_range symbol for external module 2017-01-24 16:26:14 -08:00
mm mm/slub.c: fix random_seq offset destruction 2017-02-08 15:41:43 -08:00
net l2tp: do not use udp_ioctl() 2017-02-10 15:57:34 -05:00
samples bpf: fix samples xdp_tx_iptunnel and tc_l2_redirect with fake KBUILD_MODNAME 2017-01-20 12:04:07 -05:00
scripts kbuild: modversions: add infrastructure for emitting relative CRCs 2017-02-03 08:28:25 -08:00
security selinux: fix off-by-one in setprocattr 2017-02-08 19:09:53 +11:00
sound ALSA: hda - adding a new NV HDMI/DP codec ID in the driver 2017-02-09 08:57:47 +01:00
tools perf/urgent fixes: 2017-02-03 20:42:30 +01:00
usr kbuild: initramfs cleanup, set target from Kconfig 2017-01-05 09:40:16 -08:00
virt KVM/ARM updates for 4.10-rc4 2017-01-17 15:04:59 +01:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.get_maintainer.ignore
.gitattributes .gitattributes: set git diff driver for C source code files 2016-10-07 18:46:30 -07:00
.gitignore Merge branch 'misc' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild 2016-08-02 16:48:52 -04:00
.mailmap mailmap: add codeaurora.org names for nameless email commits 2017-01-10 18:31:55 -08:00
COPYING
CREDITS CREDITS: Remove outdated address information 2016-12-21 15:21:29 -08:00
Kbuild scripts/gdb: provide linux constants 2016-05-23 17:04:14 -07:00
Kconfig
MAINTAINERS mmc: dw_mmc: Remove the public dw_mmc header file 2017-02-13 13:19:59 +01:00
Makefile Linux 4.10-rc8 2017-02-12 13:03:20 -08:00
README README: add a new README file, pointing to the Documentation/ 2016-10-24 08:12:35 -02:00

README 

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

This file was moved to Documentation/admin-guide/README.rst

Please notice that there are several guides for kernel developers and users.
These guides can be rendered in a number of formats, like HTML and PDF.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.

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.