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Finn Thain b64576cbf3 m68k/mac: Don't remap SWIM MMIO region
For reasons I don't understand, calling ioremap() then iounmap() on
the SWIM MMIO region causes a hang on 68030 (but not on 68040).

~# modprobe swim_mod
SWIM floppy driver Version 0.2 (2008-10-30)
SWIM device not found !
watchdog: BUG: soft lockup - CPU#0 stuck for 23s! [modprobe:285]
Modules linked in: swim_mod(+)
Format 00  Vector: 0064  PC: 000075aa  Status: 2000    Not tainted
ORIG_D0: ffffffff  D0: d00c0000  A2: 007c2370  A1: 003f810c
A0: 00040000  D5: d0096800  D4: d0097e00
D3: 00000001  D2: 00000003  D1: 00000000
Non-Maskable Interrupt
Modules linked in: swim_mod(+)
PC: [<000075ba>] __iounmap+0x24/0x10e
SR: 2000  SP: 007abc48  a2: 007c2370
d0: d00c0000    d1: 000001a0    d2: 00000019    d3: 00000001
d4: d0097e00    d5: d0096800    a0: 00040000    a1: 003f810c
Process modprobe (pid: 285, task=007c2370)
Frame format=0
Stack from 007abc7c:
        ffffffed 00000000 006a4060 004712e0 007abca0 000076ea d0080000 00080000
        010bb4b8 007abcd8 010ba542 d0096000 00000000 00000000 00000001 010bb59c
        00000000 007abf30 010bb4b8 0047760a 0047763c 00477612 00616540 007abcec
        0020a91a 00477600 0047760a 010bb4cc 007abd18 002092f2 0047760a 00333b06
        007abd5c 00000000 0047760a 010bb4cc 00404f90 004776b8 00000001 007abd38
        00209446 010bb4cc 0047760a 010bb4cc 0020938e 0031f8be 00616540 007abd64
Call Trace: [<000076ea>] iounmap+0x46/0x5a
 [<00080000>] shrink_page_list+0x7f6/0xe06
 [<010ba542>] swim_probe+0xe4/0x496 [swim_mod]
 [<0020a91a>] platform_drv_probe+0x20/0x5e
 [<002092f2>] driver_probe_device+0x21c/0x2b8
 [<00333b06>] mutex_lock+0x0/0x2e
 [<00209446>] __driver_attach+0xb8/0xce
 [<0020938e>] __driver_attach+0x0/0xce
 [<0031f8be>] klist_next+0x0/0xa0
 [<00207562>] bus_for_each_dev+0x74/0xba
 [<000344c0>] blocking_notifier_call_chain+0x0/0x20
 [<00333b06>] mutex_lock+0x0/0x2e
 [<00208e44>] driver_attach+0x1a/0x1e
 [<0020938e>] __driver_attach+0x0/0xce
 [<00207e26>] bus_add_driver+0x188/0x234
 [<000344c0>] blocking_notifier_call_chain+0x0/0x20
 [<00209894>] driver_register+0x58/0x104
 [<000344c0>] blocking_notifier_call_chain+0x0/0x20
 [<010bd000>] swim_init+0x0/0x2c [swim_mod]
 [<0020a7be>] __platform_driver_register+0x38/0x3c
 [<010bd028>] swim_init+0x28/0x2c [swim_mod]
 [<000020dc>] do_one_initcall+0x38/0x196
 [<000344c0>] blocking_notifier_call_chain+0x0/0x20
 [<003331cc>] mutex_unlock+0x0/0x3e
 [<00333b06>] mutex_lock+0x0/0x2e
 [<003331cc>] mutex_unlock+0x0/0x3e
 [<00333b06>] mutex_lock+0x0/0x2e
 [<003331cc>] mutex_unlock+0x0/0x3e
 [<00333b06>] mutex_lock+0x0/0x2e
 [<003331cc>] mutex_unlock+0x0/0x3e
 [<00333b06>] mutex_lock+0x0/0x2e
 [<00075008>] __free_pages+0x0/0x38
 [<000045c0>] mangle_kernel_stack+0x30/0xda
 [<000344c0>] blocking_notifier_call_chain+0x0/0x20
 [<003331cc>] mutex_unlock+0x0/0x3e
 [<00333b06>] mutex_lock+0x0/0x2e
 [<0005ced4>] do_init_module+0x42/0x266
 [<010bd000>] swim_init+0x0/0x2c [swim_mod]
 [<000344c0>] blocking_notifier_call_chain+0x0/0x20
 [<0005eda0>] load_module+0x1a30/0x1e70
 [<0000465d>] mangle_kernel_stack+0xcd/0xda
 [<00331c64>] __generic_copy_from_user+0x0/0x46
 [<0033256e>] _cond_resched+0x0/0x32
 [<00331b9c>] memset+0x0/0x98
 [<0033256e>] _cond_resched+0x0/0x32
 [<0005f25c>] SyS_init_module+0x7c/0x112
 [<00002000>] _start+0x0/0x8
 [<00002000>] _start+0x0/0x8
 [<00331c82>] __generic_copy_from_user+0x1e/0x46
 [<0005f2b2>] SyS_init_module+0xd2/0x112
 [<0000465d>] mangle_kernel_stack+0xcd/0xda
 [<00002b40>] syscall+0x8/0xc
 [<0000465d>] mangle_kernel_stack+0xcd/0xda
 [<0008c00c>] pcpu_balance_workfn+0xb2/0x40e
Code: 2200 7419 e4a9 e589 2841 d9fc 0000 1000 <2414> 7203 c282 7602 b681 6600 0096 0242 fe00 0482 0000 0000 e9c0 11c3 ed89 2642

There's no need to call ioremap() for the SWIM address range, as it lies
within the usual IO device region at 0x5000 0000, which has already been
mapped by head.S.

Remove the redundant ioremap() and iounmap() calls to fix the hang.

Cc: Laurent Vivier <lvivier@redhat.com>
Cc: stable@vger.kernel.org # v4.14+
Tested-by: Stan Johnson <userm57@yahoo.com>
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Acked-by: Laurent Vivier <lvivier@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-04-16 21:49:35 -06:00
Documentation Merge branch 'overlayfs-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs 2018-04-13 16:55:41 -07:00
LICENSES LICENSES: Add MPL-1.1 license 2018-01-06 10:59:44 -07:00
arch Fixes for bugs in futex, device tree, and userspace breakpoint traps, 2018-04-13 12:27:11 -07:00
block block: do not use interruptible wait anywhere 2018-04-14 13:54:33 -06:00
certs certs/blacklist_nohashes.c: fix const confusion in certs blacklist 2018-02-21 15:35:43 -08:00
crypto MIPS changes for 4.17 2018-04-10 11:39:22 -07:00
drivers m68k/mac: Don't remap SWIM MMIO region 2018-04-16 21:49:35 -06:00
firmware kbuild: remove all dummy assignments to obj- 2017-11-18 11:46:06 +09:00
fs Merge branch 'overlayfs-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs 2018-04-13 16:55:41 -07:00
include Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/rzhang/linux 2018-04-13 16:52:26 -07:00
init seq_file: allocate seq_file from kmem_cache 2018-04-11 10:28:36 -07:00
ipc ipc/shm.c: shm_split(): remove unneeded test for NULL shm_file_data.vm_ops 2018-04-11 10:28:38 -07:00
kernel A few clean ups and bug fixes 2018-04-12 20:54:01 -07:00
lib We decided to request the latest three patches to be merged into this 2018-04-12 13:00:44 -07:00
mm page cache: use xa_lock 2018-04-11 10:28:39 -07:00
net NFS client updates for Linux 4.17 2018-04-12 12:55:50 -07:00
samples remoteproc updates for v4.17 2018-04-10 12:09:27 -07:00
scripts asm-generic fixes for v4.17-rc1 2018-04-12 09:15:48 -07:00
security + Features 2018-04-13 15:38:53 -07:00
sound amdgpu, omap and snd regression fix 2018-04-12 20:56:10 -07:00
tools proc: fixup copyright sign 2018-04-12 20:52:25 -07:00
usr kbuild: rename built-in.o to built-in.a 2018-03-26 02:01:19 +09:00
virt KVM/ARM updates for v4.17 2018-03-28 16:09:09 +02:00
.clang-format clang-format: add configuration file 2018-04-11 10:28:35 -07:00
.cocciconfig
.get_maintainer.ignore
.gitattributes .gitattributes: set git diff driver for C source code files 2016-10-07 18:46:30 -07:00
.gitignore clang-format: add configuration file 2018-04-11 10:28:35 -07:00
.mailmap Merge candidates for 4.17 merge window 2018-04-06 17:35:43 -07:00
COPYING COPYING: use the new text with points to the license files 2018-03-23 12:41:45 -06:00
CREDITS MAINTAINERS/CREDITS: Drop METAG ARCHITECTURE 2018-03-05 16:34:24 +00:00
Kbuild Kbuild updates for v4.15 2017-11-17 17:45:29 -08:00
Kconfig License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
MAINTAINERS Changes to chrome-platform for v4.17 2018-04-13 16:20:36 -07:00
Makefile Kconfig updates for v4.17 2018-04-03 16:28:01 -07:00
README Docs: Added a pointer to the formatted docs to README 2018-03-21 09:02:53 -06:00

README

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.