linux_dsm_epyc7002/include
Doug Anderson f8c58c1136 mmc: dw_mmc: Protect read-modify-write of INTMASK with a lock
We're running into cases where our enabling of the SDIO interrupt in
dw_mmc doesn't actually take effect.  Specifically, adding patch like
this:

 +++ b/drivers/mmc/host/dw_mmc.c
 @@ -1076,6 +1076,9 @@ static void dw_mci_enable_sdio_irq(struct mmc_host *mmc, int enb)

      mci_writel(host, INTMASK,
           (int_mask | SDMMC_INT_SDIO(slot->id)));
 +    int_mask = mci_readl(host, INTMASK);
 +    if (!(int_mask & SDMMC_INT_SDIO(slot->id)))
 +      dev_err(&mmc->class_dev, "failed to enable sdio irq\n");
    } else {

...actually triggers the error message.  That's because the
dw_mci_enable_sdio_irq() unsafely does a read-modify-write of the
INTMASK register.

We can't just use the standard host->lock since that lock is not irq
safe and mmc_signal_sdio_irq() (called from interrupt context) calls
dw_mci_enable_sdio_irq().  Add a new irq-safe lock to protect INTMASK.

An alternate solution to this is to punt mmc_signal_sdio_irq() to the
tasklet and then protect INTMASK modifications by the standard host
lock.  This seemed like a bit more of a high-latency change.

Reported-by: Bing Zhao <bzhao@marvell.com>
Signed-off-by: Doug Anderson <dianders@chromium.org>
Reviewed-by: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2015-01-19 09:56:05 +01:00
..
acpi ACPI / processor: Convert apic_id to phys_id to make it arch agnostic 2015-01-05 23:32:42 +01:00
asm-generic mm: mmu_gather: use tlb->end != 0 only for TLB invalidation 2015-01-13 15:20:40 +13:00
clocksource
crypto crypto: af_alg - add user space interface for AEAD 2014-12-05 23:56:55 +08:00
drm Revert "drm/gem: Warn on illegal use of the dumb buffer interface v2" 2014-12-24 13:13:22 +10:00
dt-bindings Merge branch 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/evalenti/linux-soc-thermal into thermal-soc 2014-12-21 22:49:12 +08:00
keys
kvm arm/arm64: KVM: Require in-kernel vgic for the arch timers 2014-12-15 11:50:42 +01:00
linux mmc: dw_mmc: Protect read-modify-write of INTMASK with a lock 2015-01-19 09:56:05 +01:00
math-emu
media
memory
misc
net Here's just a single fix - a revert of a patch that broke the 2015-01-06 13:29:27 -05:00
pcmcia
ras
rdma IB/core: Implement support for MMU notifiers regarding on demand paging regions 2014-12-15 18:13:36 -08:00
rxrpc
scsi SCSI for-linus on 20141220 2014-12-20 13:42:57 -08:00
soc Merge branch 'at91/cleanup5' into next/drivers 2014-12-08 18:29:20 +01:00
sound ALSA: pcm: Fix kerneldoc for params_*() functions 2014-12-30 16:41:11 +01:00
target target: Drop left-over fabric_max_sectors attribute 2015-01-09 15:22:05 -08:00
trace SCSI for-linus on 20141220 2014-12-20 13:42:57 -08:00
uapi Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2015-01-15 11:17:37 +13:00
video
xen x86/xen: properly retrieve NMI reason 2015-01-13 09:39:50 +00:00
Kbuild