[tip:x86/urgent] x86/hyper-v: Fix definition of HV_MAX_FLUSH_REP_COUNT

From: tip-bot for Lan Tianyu
Date: Thu Feb 28 2019 - 06:04:16 EST


Commit-ID: 9cd05ad2910b55238e3c720c99ad896dc538301b
Gitweb: https://git.kernel.org/tip/9cd05ad2910b55238e3c720c99ad896dc538301b
Author: Lan Tianyu <Tianyu.Lan@xxxxxxxxxxxxx>
AuthorDate: Mon, 25 Feb 2019 22:31:14 +0800
Committer: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
CommitDate: Thu, 28 Feb 2019 11:58:29 +0100

x86/hyper-v: Fix definition of HV_MAX_FLUSH_REP_COUNT

The max flush rep count of HvFlushGuestPhysicalAddressList hypercall is
equal with how many entries of union hv_gpa_page_range can be populated
into the input parameter page.

The code lacks parenthesis around PAGE_SIZE - 2 * sizeof(u64) which results
in bogus computations. Add them.

Fixes: cc4edae4b924 ("x86/hyper-v: Add HvFlushGuestAddressList hypercall support")
Signed-off-by: Lan Tianyu <Tianyu.Lan@xxxxxxxxxxxxx>
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: kys@xxxxxxxxxxxxx
Cc: haiyangz@xxxxxxxxxxxxx
Cc: sthemmin@xxxxxxxxxxxxx
Cc: sashal@xxxxxxxxxx
Cc: bp@xxxxxxxxx
Cc: hpa@xxxxxxxxx
Cc: gregkh@xxxxxxxxxxxxxxxxxxx
Cc: devel@xxxxxxxxxxxxxxxxxxxxxx
Cc: stable@xxxxxxxxxxxxxxx
Link: https://lkml.kernel.org/r/20190225143114.5149-1-Tianyu.Lan@xxxxxxxxxxxxx
---
arch/x86/include/asm/hyperv-tlfs.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/include/asm/hyperv-tlfs.h b/arch/x86/include/asm/hyperv-tlfs.h
index 705dafc2d11a..2bdbbbcfa393 100644
--- a/arch/x86/include/asm/hyperv-tlfs.h
+++ b/arch/x86/include/asm/hyperv-tlfs.h
@@ -841,7 +841,7 @@ union hv_gpa_page_range {
* count is equal with how many entries of union hv_gpa_page_range can
* be populated into the input parameter page.
*/
-#define HV_MAX_FLUSH_REP_COUNT (PAGE_SIZE - 2 * sizeof(u64) / \
+#define HV_MAX_FLUSH_REP_COUNT ((PAGE_SIZE - 2 * sizeof(u64)) / \
sizeof(union hv_gpa_page_range))

struct hv_guest_mapping_flush_list {