A-Team_Digital_Solutions/android_kernel_motorola_sm6375
Watch
2
0
Fork
You've already forked android_kernel_motorola_sm6375
 0
mirror of https://github.com/BobTheBlinker/android_kernel_motorola_sm6375.git synced 2026-10-11 07:03:09 -04:00
Code Issues Projects Releases Packages Wiki Activity

soc: qcom: smp2p: Add memory barrier for irq_pending

Browse source 
There is a very tight race where the irq_retrigger function is run
on one cpu and the actual retrigger softirq is running on a second
cpu. When this happens, there may be a chance that the second cpu
will not see the updated irq_pending value from first cpu.

Add a memory barrier to ensure that irq_pending is read correctly.

Change-Id: I3dd185decc4f050bd57c0b6558f417ead2a3aa5a
Signed-off-by: Chris Lew <clew@codeaurora.org>
This commit is contained in:
Chris Lew 2020-11-06 14:37:02 -08:00
commit f2197a20e8
1 changed files with 8 additions and 0 deletions
Download patch file Download diff file Expand all files Collapse all files

8
drivers/soc/qcom/smp2p.c
View file

@ -270,6 +270,9 @@ static void qcom_smp2p_notify_in(struct qcom_smp2p *smp2p)
status = val ^ entry->last_value;
entry->last_value = val;
/* Ensure irq_pending is read correctly */
mb();
status |= *entry->irq_pending;
SMP2P_INFO("%d:\t%s: status:%0lx val:%0x\n",
@ -391,6 +394,11 @@ static int smp2p_retrigger_irq(struct irq_data *irqd)
SMP2P_INFO("%d: %s: %lu\n", entry->smp2p->remote_pid, entry->name, irq);
set_bit(irq, entry->irq_pending);
/* Ensure irq_pending is visible to all cpus that retried interrupt
* can run on
*/
mb();
return 0;
}