svn commit: r343791 - head/sys/powerpc/pseries

[Leandro Lupori]

Author: luporl
Date: Tue Feb  5 18:16:14 2019
New Revision: 343791
URL: https://svnweb.freebsd.org/changeset/base/343791

Log:
  [ppc64] llan: fix fatal kernel trap when system is low on memory
  
  When running several builders in parallel, on QEMU, with 8GB of
  memory, a fatal kernel trap (0x300 (data storage interrupt))
  caused by llan driver is sometimes observed, when the system
  starts to run out of swap space.
  
  This happens because, at llan_intr(), a phyp call to add a
  logical LAN buffer is always made when llan_add_rxbuf() fails,
  even if it fails to allocate a new buffer.
  
  PR:	235489
  Reviewed by:	jhibbits
  Differential Revision:	https://reviews.freebsd.org/D19084

Modified:
  head/sys/powerpc/pseries/phyp_llan.c

Modified: head/sys/powerpc/pseries/phyp_llan.c
==============================================================================
--- head/sys/powerpc/pseries/phyp_llan.c	Tue Feb  5 18:11:15 2019	(r343790)
+++ head/sys/powerpc/pseries/phyp_llan.c	Tue Feb  5 18:16:14 2019	(r343791)
@@ -386,8 +386,6 @@ restart:
 		/* llan_add_rxbuf does DMA sync and unload as well as requeue */
 		if (llan_add_rxbuf(sc, rx) != 0) {
 			if_inc_counter(sc->ifp, IFCOUNTER_IERRORS, 1);
-			phyp_hcall(H_ADD_LOGICAL_LAN_BUFFER, sc->unit,
-			    rx->rx_bufdesc);
 			continue;
 		}