[armhf] mm: Export __sync_icache_dcache() for xen-privcmd (fixes FTBFS)

debian/changelog

@@ -8,6 +8,7 @@ linux (4.18~rc4-1~exp1) UNRELEASED; urgency=medium
     - linux-perf: Use Python 3 for scripts
   * autofs: rename 'autofs' module back to 'autofs4' (Closes: #902946)
   * udeb: Move of_mdio to nic-shared-modules (Closes: #903587)
+  * [armhf] mm: Export __sync_icache_dcache() for xen-privcmd (fixes FTBFS)
 
  -- Ben Hutchings <ben@decadent.org.uk>  Fri, 06 Jul 2018 20:55:47 +0100
 

debian/patches/bugfix/arm/arm-mm-export-__sync_icache_dcache-for-xen-privcmd.patch

@@ -0,0 +1,31 @@
+From: Ben Hutchings <ben@decadent.org.uk>
+Date: Wed, 11 Jul 2018 23:40:55 +0100
+Subject: ARM: mm: Export __sync_icache_dcache() for xen-privcmd
+Forwarded: https://marc.info/?l=linux-arm-kernel&m=153134944429241
+
+The xen-privcmd driver, which can be modular, calls set_pte_at()
+which in turn may call __sync_icache_dcache().
+
+The call to __sync_icache_dcache() may be optimised out because it is
+conditional on !pte_special(), and xen-privcmd calls pte_mkspecial().
+However, in a non-LPAE configuration there is no "special" bit and the
+call is really unconditional.
+
+Fixes: 3ad0876554ca ("xen/privcmd: add IOCTL_PRIVCMD_MMAP_RESOURCE")
+Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
+---
+ arch/arm/mm/flush.c | 1 +
+ 1 file changed, 1 insertion(+)
+
+diff --git a/arch/arm/mm/flush.c b/arch/arm/mm/flush.c
+index 58469623b015..5345f86c56d2 100644
+--- a/arch/arm/mm/flush.c
++++ b/arch/arm/mm/flush.c
+@@ -295,6 +295,7 @@ void __sync_icache_dcache(pte_t pteval)
+ 	if (pte_exec(pteval))
+ 		__flush_icache_all();
+ }
++EXPORT_SYMBOL_GPL(__sync_icache_dcache);
+ #endif
+ 
+ /*

debian/patches/series

@@ -65,6 +65,7 @@ bugfix/x86/perf-tools-fix-unwind-build-on-i386.patch
 bugfix/sh/sh-boot-do-not-use-hyphen-in-exported-variable-name.patch
 bugfix/x86/mmap-remember-the-map_fixed-flag-as-vm_fixed.patch
 bugfix/x86/mmap-add-an-exception-to-the-stack-gap-for-hotspot-jvm.patch
+bugfix/arm/arm-mm-export-__sync_icache_dcache-for-xen-privcmd.patch
 
 # Arch features
 features/mips/MIPS-increase-MAX-PHYSMEM-BITS-on-Loongson-3-only.patch