powerpc/sysdev/ipic: check primary_ipic NULL pointer before using it

ipic_get_mcp_status() is used by targets implementing NMI
watchdog in target specific machine check handler in order
to known whether a machine check results from a watchdog
NMI reset.

In case of very early machine check, primary_ipic pointer
might not have been set yet, so ipic_get_mcp_status() needs
to check it for nullity before using it.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This commit is contained in:
Christophe Leroy 2018-08-27 08:27:27 +00:00 committed by Michael Ellerman
parent 37e9c674e7
commit 6beb3381b1

View File

@ -846,7 +846,7 @@ void ipic_disable_mcp(enum ipic_mcp_irq mcp_irq)
u32 ipic_get_mcp_status(void)
{
return ipic_read(primary_ipic->regs, IPIC_SERSR);
return primary_ipic ? ipic_read(primary_ipic->regs, IPIC_SERSR) : 0;
}
void ipic_clear_mcp_status(u32 mask)