From: Evgeny Yakovlev Date: Thu, 18 Jul 2019 16:14:23 +0000 (+0300) Subject: i386/acpi: fix gint overflow in crs_range_compare X-Git-Url: http://xenbits.xensource.com/gitweb?a=commitdiff_plain;h=21e2acd583126db94f6d881005cd58e835160582;p=people%2Fpauldu%2Fqemu.git 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 --- diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c index d281ffa89e..e7b756b51b 100644 --- a/hw/i386/acpi-build.c +++ b/hw/i386/acpi-build.c @@ -755,10 +755,16 @@ 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; + } } /*