From: Jan Beulich <jbeulich@suse.com>
Date: Tue, 4 Jan 2022 09:13:06 +0000 (+0100)
Subject: x86/EPT: squash meaningless TLB flush
X-Git-Tag: archive/raspbian/4.17.0-1+rpi1^2~33^2~1177
X-Git-Url: https://dgit.raspbian.org/?a=commitdiff_plain;h=4a59e6bb3a96f5ebca95d162b2a81b3e68b076a2;p=xen.git

x86/EPT: squash meaningless TLB flush

ept_free_entry() gets called after a flush was already issued, if one is
necessary in the first place. That behavior is similar to NPT, which
also doesn't have any further flush in p2m_free_entry(). (Furthermore,
the function being recursive, in case of recursiveness way too many
flushes would have been issued.)

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
---

diff --git a/xen/arch/x86/mm/p2m-ept.c b/xen/arch/x86/mm/p2m-ept.c
index a4f5fc4b0d..b7ee441d45 100644
--- a/xen/arch/x86/mm/p2m-ept.c
+++ b/xen/arch/x86/mm/p2m-ept.c
@@ -246,8 +246,7 @@ static void ept_free_entry(struct p2m_domain *p2m, ept_entry_t *ept_entry, int l
             ept_free_entry(p2m, epte + i, level - 1);
         unmap_domain_page(epte);
     }
-    
-    p2m_tlb_flush_sync(p2m);
+
     p2m_free_ptp(p2m, mfn_to_page(_mfn(ept_entry->mfn)));
 }