From d7e9b19f0b4ae99e1a5bfe8f190847e7f1785db4 Mon Sep 17 00:00:00 2001 From: Evgeny Yakovlev Date: Thu, 18 Jul 2019 19:14:23 +0300 Subject: [PATCH] i386/acpi: fix gint overflow in crs_range_compare When very large regions (32GB sized in our case, PCI pass-through of GPUs) are compared substraction result does not fit into gint. As a result crs_replace_with_free_ranges does not get sorted ranges and incorrectly computes PCI64 free space regions. Which then makes linux guest complain about device and PCI64 hole intersection and device becomes unusable. Fix that by returning exactly fitting ranges. Also fix indentation of an entire crs_replace_with_free_ranges to make checkpatch happy. Cc: qemu-stable@nongnu.org Signed-off-by: Evgeny Yakovlev Message-Id: <1563466463-26012-1-git-send-email-wrfsh@yandex-team.ru> Signed-off-by: Evgeny Yakovlev (cherry picked from commit 21e2acd583126db94f6d881005cd58e835160582) Signed-off-by: Michael Roth --- hw/i386/acpi-build.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c index ede27ab3c46..bf59c475bef 100644 --- a/hw/i386/acpi-build.c +++ b/hw/i386/acpi-build.c @@ -743,10 +743,16 @@ static void crs_range_set_free(CrsRangeSet *range_set) static gint crs_range_compare(gconstpointer a, gconstpointer b) { - CrsRangeEntry *entry_a = *(CrsRangeEntry **)a; - CrsRangeEntry *entry_b = *(CrsRangeEntry **)b; + CrsRangeEntry *entry_a = *(CrsRangeEntry **)a; + CrsRangeEntry *entry_b = *(CrsRangeEntry **)b; - return (int64_t)entry_a->base - (int64_t)entry_b->base; + if (entry_a->base < entry_b->base) { + return -1; + } else if (entry_a->base > entry_b->base) { + return 1; + } else { + return 0; + } } /* -- 2.39.5