[PATCH v2 03/10] m68k/mac: Don't remap SWIM MMIO region
From: Finn Thain
Date: Wed Apr 11 2018 - 20:52:22 EST
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@xxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx # v4.14+
Tested-by: Stan Johnson <userm57@xxxxxxxxx>
Signed-off-by: Finn Thain <fthain@xxxxxxxxxxxxxxxxxxx>
Acked-by: Laurent Vivier <lvivier@xxxxxxxxxx>
---
drivers/block/swim.c | 10 +++-------
1 file changed, 3 insertions(+), 7 deletions(-)
diff --git a/drivers/block/swim.c b/drivers/block/swim.c
index 64e066eba72e..92f0cddc597e 100644
--- a/drivers/block/swim.c
+++ b/drivers/block/swim.c
@@ -911,7 +911,7 @@ static int swim_probe(struct platform_device *dev)
goto out;
}
- swim_base = ioremap(res->start, resource_size(res));
+ swim_base = (struct swim __iomem *)res->start;
if (!swim_base) {
ret = -ENOMEM;
goto out_release_io;
@@ -923,7 +923,7 @@ static int swim_probe(struct platform_device *dev)
if (!get_swim_mode(swim_base)) {
printk(KERN_INFO "SWIM device not found !\n");
ret = -ENODEV;
- goto out_iounmap;
+ goto out_release_io;
}
/* set platform driver data */
@@ -931,7 +931,7 @@ static int swim_probe(struct platform_device *dev)
swd = kzalloc(sizeof(struct swim_priv), GFP_KERNEL);
if (!swd) {
ret = -ENOMEM;
- goto out_iounmap;
+ goto out_release_io;
}
platform_set_drvdata(dev, swd);
@@ -945,8 +945,6 @@ static int swim_probe(struct platform_device *dev)
out_kfree:
kfree(swd);
-out_iounmap:
- iounmap(swim_base);
out_release_io:
release_mem_region(res->start, resource_size(res));
out:
@@ -974,8 +972,6 @@ static int swim_remove(struct platform_device *dev)
for (drive = 0; drive < swd->floppy_count; drive++)
floppy_eject(&swd->unit[drive]);
- iounmap(swd->base);
-
res = platform_get_resource(dev, IORESOURCE_MEM, 0);
if (res)
release_mem_region(res->start, resource_size(res));
--
2.16.1