From: Arnd Bergmann <arnd@arndb.de>
Date: Thu, 10 Aug 2017 14:14:39 +0200
Subject: kvm: avoid uninitialized-variable warnings
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Patch-mainline: v4.14-rc1
Git-commit: 076b925d51e83c1939bf796c4c5a33f482f986b3
References: bsc#1077761

When PAGE_OFFSET is not a compile-time constant, we run into
warnings from the use of kvm_is_error_hva() that the compiler
cannot optimize out:

arch/arm/kvm/../../../virt/kvm/kvm_main.c: In function '__kvm_gfn_to_hva_cache_init':
arch/arm/kvm/../../../virt/kvm/kvm_main.c:1978:14: error: 'nr_pages_avail' may be used uninitialized in this function [-Werror=maybe-uninitialized]
arch/arm/kvm/../../../virt/kvm/kvm_main.c: In function 'gfn_to_page_many_atomic':
arch/arm/kvm/../../../virt/kvm/kvm_main.c:1660:5: error: 'entry' may be used uninitialized in this function [-Werror=maybe-uninitialized]

This adds fake initializations to the two instances I ran into.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Acked-by: Alexander Graf <agraf@suse.de>
---
 virt/kvm/kvm_main.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -1609,7 +1609,7 @@
 			    struct page **pages, int nr_pages)
 {
 	unsigned long addr;
-	gfn_t entry;
+	gfn_t entry = 0;
 
 	addr = gfn_to_hva_many(slot, gfn, &entry);
 	if (kvm_is_error_hva(addr))
@@ -1928,6 +1928,7 @@
 		 * verify that the entire region is valid here.
 		 */
 		while (start_gfn <= end_gfn) {
+			nr_pages_avail = 0;
 			ghc->memslot = __gfn_to_memslot(slots, start_gfn);
 			ghc->hva = gfn_to_hva_many(ghc->memslot, start_gfn,
 						   &nr_pages_avail);