diff options
| author | Dimitris Papastamos <dimitris.papastamos@arm.com> | 2018-01-02 15:53:01 +0000 |
|---|---|---|
| committer | Dimitris Papastamos <dimitris.papastamos@arm.com> | 2018-01-11 10:26:15 +0000 |
| commit | 780edd86a0b413c3620c5c42fd123a78b5b1587a (patch) | |
| tree | db65d33adc45ff13b8dc2a6eb5252a94d1405057 /lib | |
| parent | a1781a211a53df6a24345d774c0f2eaa5b675ca8 (diff) | |
Use PFR0 to identify need for mitigation of CVE-2017-5915
If the CSV2 field reads as 1 then branch targets trained in one
context cannot affect speculative execution in a different context.
In that case skip the workaround on Cortex A75.
Change-Id: I4d5504cba516a67311fb5f0657b08f72909cbd38
Signed-off-by: Dimitris Papastamos <dimitris.papastamos@arm.com>
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/cpus/aarch64/cortex_a75.S | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/lib/cpus/aarch64/cortex_a75.S b/lib/cpus/aarch64/cortex_a75.S index 1a9d9049..9b54b48f 100644 --- a/lib/cpus/aarch64/cortex_a75.S +++ b/lib/cpus/aarch64/cortex_a75.S @@ -13,8 +13,18 @@ func cortex_a75_reset_func #if IMAGE_BL31 && WORKAROUND_CVE_2017_5715 + mrs x0, id_aa64pfr0_el1 + ubfx x0, x0, #ID_AA64PFR0_CSV2_SHIFT, #ID_AA64PFR0_CSV2_LENGTH + /* + * If the field equals to 1 then branch targets trained in one + * context cannot affect speculative execution in a different context. + */ + cmp x0, #1 + beq 1f + adr x0, workaround_bpiall_vbar0_runtime_exceptions msr vbar_el3, x0 +1: #endif #if ENABLE_AMU |