Following kernel panic is observed on 64bit machine while loading
the driver. It is fixed if we pass dynamically allocated memory to
SDIO for DMA.

BUG: unable to handle kernel paging request at ffffeb04000172e0
IP: sg_miter_stop+0x56/0x70
PGD 0 P4D 0
Oops: 0000 [#1] SMP PTI
Modules linked in: rsi_sdio(OE+) rsi_91x(OE) btrsi(OE) rfcomm bluetooth
ecdh_generic mac80211 mmc_block fuse xt_CHECKSUM iptable_mangle
drm_kms_helper mmc_core serio_raw drm firewire_ohci tg3
CPU: 0 PID: 4003 Comm: insmod Tainted: G           OE    4.16.0-rc1+ #27
Hardware name: Dell Inc. Latitude E5500                  /0DW634, BIOS
A19 06/13/2013
RIP: 0010:sg_miter_stop+0x56/0x70
RSP: 0018:ffff88007d003e78 EFLAGS: 00010002
RAX: 0000000000000003 RBX: 0000000000000004 RCX: 0000000000000000
RDX: ffffeb04000172c0 RSI: ffff88002f58002c RDI: ffff88007d003e80
RBP: 0000000000000004 R08: ffff88007d003e80 R09: 0000000000000008
R10: 0000000000000003 R11: 0000000000000001 R12: 0000000000000004
R13: ffff88002f580028 R14: 0000000000000000 R15: 0000000000000004
FS:  00007f35c29db700(0000) GS:ffff88007d000000(0000)
knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffeb04000172e0 CR3: 000000007038e000 CR4: 00000000000406f0
Call Trace:
<IRQ>
sg_copy_buffer+0xc6/0xf0
sdhci_tasklet_finish+0x170/0x260 [sdhci]
tasklet_action+0xf4/0x100
__do_softirq+0xef/0x26e
irq_exit+0xbe/0xd0
do_IRQ+0x4a/0xc0
common_interrupt+0xa2/0xa2
</IRQ>
Signed-off-by: Amitkumar Karwar <amit.karwar@redpinesignals.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>