Sun Sep 1 14:03:02 2019 UTC ()
Pull up following revision(s) (requested by rin in ticket #146):
sys/arch/arm/conf/Makefile.arm: revision 1.50
sys/dev/usb/if_axe.c: revision 1.120
PR kern/54486
Workaround for alignment faults on ARMv6+, at least occur with
axe(4) and athn(4) drivers.
For ARMv6+, unaligned access is enabled by default. However, it
cannot be used for non-cacheable memory, which is used as DMA
buffers. This results in alignment faults above. A real fix is
to use cacheable memory as DMA buffers. However, it breaks some
drivers, awge(4) and vchiq(4) at least.
Until we figure out problems and fix them, we choose a fail-safe
workaround here; forbid unaligned memory access for whole kernel.
Affects on performance is negligibly small as far as we can see.
XXX
pullup netbsd-9
-
PR kern/54486
Revert workaround introduced in rev 1.94:
http://cvsweb.netbsd.org/bsdweb.cgi/src/sys/dev/usb/if_axe.c#rev1.94
This is a problem specific to ARMv6+, and addressed by
arch/arm/conf/Makefile.arm rev 1.50:
http://cvsweb.netbsd.org/bsdweb.cgi/src/sys/arch/arm/conf/Makefile.arm#rev1.50
XXX
pullup netbsd-9
(martin)
diff -r1.49 -r1.49.4.1 src/sys/arch/arm/conf/Makefile.arm
diff -r1.102.2.1 -r1.102.2.2 src/sys/dev/usb/if_axe.c
--- src/sys/arch/arm/conf/Makefile.arm 2018/09/22 12:24:01 1.49
+++ src/sys/arch/arm/conf/Makefile.arm 2019/09/01 14:03:02 1.49.4.1
@@ -1,4 +1,4 @@
-# $NetBSD: Makefile.arm,v 1.49 2018/09/22 12:24:01 rin Exp $
+# $NetBSD: Makefile.arm,v 1.49.4.1 2019/09/01 14:03:02 martin Exp $
# Makefile for NetBSD
#
@@ -52,6 +52,26 @@
CPPFLAGS.cpufunc_asm_armv6.S+= -mcpu=arm1136j-s
CPPFLAGS.cpufunc_asm_arm11.S+= -mcpu=arm1136j-s
CPPFLAGS.cpufunc_asm_xscale.S+= -mcpu=xscale
+
+.if !empty(MACHINE_ARCH:Mearmv6*) || !empty(MACHINE_ARCH:Mearmv7*)
+# XXX
+#
+# Workaround for alignment faults on ARMv6+, at least occur with
+# axe(4) and athn(4) drivers.
+#
+# For ARMv6+, unaligned access is enabled by default. However, it
+# cannot be used for non-cacheable memory, which is used as DMA
+# buffers. This results in alignment faults above. A real fix is
+# to use cacheable memory as DMA buffers. However, it breaks some
+# drivers, awge(4) and vchiq(4) at least.
+#
+# Until we figure out problems and fix them, we choose a fail-safe
+# workaround here; forbid unaligned memory access for whole kernel.
+# Affects on performance is negligibly small as far as we can see.
+#
+# See PR kern/54486 for more details.
+CFLAGS+= -mno-unaligned-access
+.endif
##
## (3) libkern and compat
--- src/sys/dev/usb/if_axe.c 2019/09/01 13:00:36 1.102.2.1
+++ src/sys/dev/usb/if_axe.c 2019/09/01 14:03:02 1.102.2.2
@@ -1,4 +1,4 @@
-/* $NetBSD: if_axe.c,v 1.102.2.1 2019/09/01 13:00:36 martin Exp $ */
+/* $NetBSD: if_axe.c,v 1.102.2.2 2019/09/01 14:03:02 martin Exp $ */
/* $OpenBSD: if_axe.c,v 1.137 2016/04/13 11:03:37 mpi Exp $ */
/*
@@ -87,7 +87,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: if_axe.c,v 1.102.2.1 2019/09/01 13:00:36 martin Exp $");
+__KERNEL_RCSID(0, "$NetBSD: if_axe.c,v 1.102.2.2 2019/09/01 14:03:02 martin Exp $");
#ifdef _KERNEL_OPT
#include "opt_usb.h"
@@ -1038,18 +1038,7 @@
break;
}
-#if !defined(__NO_STRICT_ALIGNMENT) && __GNUC_PREREQ__(6, 1)
- /*
- * XXX hdr is 2-byte aligned in buf, not 4-byte.
- * For some architectures, __builtin_memcpy() of
- * GCC 6 attempts to copy sizeof(hdr) = 4 bytes
- * at onece, which results in alignment error.
- */
- hdr.len = *(uint16_t *)buf;
- hdr.ilen = *(uint16_t *)(buf + sizeof(uint16_t));
-#else
memcpy(&hdr, buf, sizeof(hdr));
-#endif
DPRINTFN(20, "total_len %#jx len %jx ilen %#jx",
total_len,