x86/hyper-v: Fix definition of HV_MAX_FLUSH_REP_COUNT

Lan Tianyu · KAGA-KOKO · commit 9cd05ad2910b · 2019-02-28T11:58:29.000+01:00
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: cc4edae ("x86/hyper-v: Add HvFlushGuestAddressList hypercall support") Signed-off-by: Lan Tianyu <Tianyu.Lan@microsoft.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: kys@microsoft.com Cc: haiyangz@microsoft.com Cc: sthemmin@microsoft.com Cc: sashal@kernel.org Cc: bp@alien8.de Cc: hpa@zytor.com Cc: gregkh@linuxfoundation.org Cc: devel@linuxdriverproject.org Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20190225143114.5149-1-Tianyu.Lan@microsoft.com
diff --git 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 {
