korg/linux
0
0
Fork 0
mirror of https://mirrors.bfsu.edu.cn/git/linux.git synced 2024-12-14 06:24:53 +08:00
Code Issues Packages Projects Releases Wiki Activity

arm64: Drop early setting of MDSCR_EL2.TPMS

Browse Source 
When running VHE, we set MDSCR_EL2.TPMS very early on to force
the trapping of EL1 SPE accesses to EL2.

However:
- we are running with HCR_EL2.{E2H,TGE}={1,1}, meaning that there
  is no EL1 to trap from

- before entering a guest, we call kvm_arm_setup_debug(), which
  sets MDCR_EL2_TPMS in the per-vcpu shadow mdscr_el2, which gets
  applied on entry by __activate_traps_common().

The early setting of MDSCR_EL2.TPMS is therefore useless and can
be dropped.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20210208095732.3267263-7-maz@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
This commit is contained in:
Marc Zyngier 2021-02-08 09:57:15 +00:00 committed by Will Deacon
parent 0c93df9622
commit c6f8c92f3f
1 changed files with 0 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

3
arch/arm64/include/asm/el2_setup.h
View File

@ -66,9 +66,6 @@
mov x0, #(MDCR_EL2_E2PB_MASK << MDCR_EL2_E2PB_SHIFT)
orr x2, x2, x0 // If we don't have VHE, then
// use EL1&0 translation.
.else
orr x2, x2, #MDCR_EL2_TPMS // For VHE, use EL2 translation
// and disable access from EL1
.endif
.Lskip_spe_\@: