The patch below does not apply to the 4.14-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 13bcb80b7ee79431fce361e060611134cb19e209 Mon Sep 17 00:00:00 2001

From: Zhenyu Wang zhenyuw@linux.intel.com Date: Wed, 20 Feb 2019 16:25:04 +0800 Subject: [PATCH] drm/i915/gvt: Fix MI_FLUSH_DW parsing with correct index check

When MI_FLUSH_DW post write hw status page in index mode, the index value is in dword step and turned into address offset in cmd dword1. As status page size is 4K, so can't exceed that.

This fixed upper bound check in cmd parser code which incorrectly stopped VM for reason of invalid MI_FLUSH_DW write index.

v2: - Fix upper bound as 4K page size because index value is address offset.

Fixes: be1da7070aea ("drm/i915/gvt: vGPU command scanner") Cc: stable@vger.kernel.org # v4.10+ Cc: "Zhao, Yan Y" yan.y.zhao@intel.com Reviewed-by: Yan Zhao yan.y.zhao@intel.com Signed-off-by: Zhenyu Wang zhenyuw@linux.intel.com

diff --git a/drivers/gpu/drm/i915/gvt/cmd_parser.c b/drivers/gpu/drm/i915/gvt/cmd_parser.c index 77ae634eb11c..bd95fd6b4ac8 100644 --- a/drivers/gpu/drm/i915/gvt/cmd_parser.c +++ b/drivers/gpu/drm/i915/gvt/cmd_parser.c @@ -1446,7 +1446,7 @@ static inline int cmd_address_audit(struct parser_exec_state *s, }

if (index_mode) { - if (guest_gma >= I915_GTT_PAGE_SIZE / sizeof(u64)) { + if (guest_gma >= I915_GTT_PAGE_SIZE) { ret = -EFAULT; goto err; }