andrius
/
arm-trusted-firmware
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

Fixup `SMCCC_ARCH_FEATURES` semantics 

When querying `SMCCC_ARCH_WORKAROUND_1` through `SMCCC_ARCH_FEATURES`,
return either:
  * -1 to indicate the PE on which `SMCCC_ARCH_FEATURES` is called
    requires firmware mitigation for CVE-2017-5715 but the mitigation
    is not compiled in.
  * 0 to indicate that firmware mitigation is required, or
  * 1 to indicate that no firmware mitigation is required.

This patch complies with v1.2 of the firmware interfaces
specification (ARM DEN 0070A).

Change-Id: Ibc32d6620efdac6c340758ec502d95554a55f02a
Signed-off-by: Dimitris Papastamos <dimitris.papastamos@arm.com>
This commit is contained in:
Dimitris Papastamos 2018-03-12 14:47:09 +00:00
parent 3991a6a49f
commit a205a56ea8
9 changed files with 88 additions and 17 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
bl31/bl31.mk
View File

@ -61,8 +61,8 @@ BL31_SOURCES += lib/extensions/sve/sve.c
endif
ifeq (${WORKAROUND_CVE_2017_5715},1)
BL31_SOURCES += lib/cpus/aarch64/workaround_cve_2017_5715_mmu.S \
lib/cpus/aarch64/workaround_cve_2017_5715_bpiall.S
BL31_SOURCES += lib/cpus/aarch64/workaround_cve_2017_5715_bpiall.S \
lib/cpus/aarch64/workaround_cve_2017_5715_mmu.S
endif
BL31_LINKERFILE := bl31/bl31.ld.S

25
include/lib/cpus/aarch64/cpu_macros.S
View File

@ -1,5 +1,5 @@
/*
* Copyright (c) 2014-2017, ARM Limited and Contributors. All rights reserved.
* Copyright (c) 2014-2018, ARM Limited and Contributors. All rights reserved.
*
* SPDX-License-Identifier: BSD-3-Clause
*/
@ -46,6 +46,8 @@ CPU_MIDR: /* cpu_ops midr */
CPU_RESET_FUNC: /* cpu_ops reset_func */
.space 8
#endif
CPU_EXTRA1_FUNC:
.space 8
#ifdef IMAGE_BL31 /* The power down core and cluster is needed only in BL31 */
CPU_PWR_DWN_OPS: /* cpu_ops power down functions */
.space (8 * CPU_MAX_PWR_DWN_OPS)
@ -113,6 +115,10 @@ CPU_OPS_SIZE = .
* _resetfunc:
* Reset function for the CPU. If there's no CPU reset function,
* specify CPU_NO_RESET_FUNC
* _extra1:
* This is a placeholder for future per CPU operations. Currently,
* some CPUs use this entry to set a test function to determine if
* the workaround for CVE-2017-5715 needs to be applied or not.
* _power_down_ops:
* Comma-separated list of functions to perform power-down
* operatios on the CPU. At least one, and up to
@ -122,8 +128,8 @@ CPU_OPS_SIZE = .
* CPU_MAX_PWR_DWN_OPS functions, the last specified one will be
* used to handle power down at subsequent levels
*/
.macro declare_cpu_ops _name:req, _midr:req, _resetfunc:req, \
_power_down_ops:vararg
.macro declare_cpu_ops_base _name:req, _midr:req, _resetfunc:req, \
_extra1:req, _power_down_ops:vararg
.section cpu_ops, "a"
.align 3
.type cpu_ops_\_name, %object
@ -131,6 +137,7 @@ CPU_OPS_SIZE = .
#if defined(IMAGE_AT_EL3)
.quad \_resetfunc
#endif
.quad \_extra1
#ifdef IMAGE_BL31
1:
/* Insert list of functions */
@ -187,6 +194,18 @@ CPU_OPS_SIZE = .
#endif
.endm
.macro declare_cpu_ops _name:req, _midr:req, _resetfunc:req, \
_power_down_ops:vararg
declare_cpu_ops_base \_name, \_midr, \_resetfunc, 0, \
\_power_down_ops
.endm
.macro declare_cpu_ops_workaround_cve_2017_5715 _name:req, _midr:req, \
_resetfunc:req, _extra1:req, _power_down_ops:vararg
declare_cpu_ops_base \_name, \_midr, \_resetfunc, \
\_extra1, \_power_down_ops
.endm
#if REPORT_ERRATA
/*
* Print status of a CPU errata

12
include/lib/cpus/workaround_cve_2017_5715.h Normal file
View File

@ -0,0 +1,12 @@
/*
* Copyright (c) 2018, ARM Limited and Contributors. All rights reserved.
*
* SPDX-License-Identifier: BSD-3-Clause
*/
#ifndef __WORKAROUND_CVE_2017_5715_H__
#define __WORKAROUND_CVE_2017_5715_H__
int check_workaround_cve_2017_5715(void);
#endif /* __WORKAROUND_CVE_2017_5715_H__ */

4
lib/cpus/aarch64/cortex_a57.S
View File

@ -555,8 +555,8 @@ func cortex_a57_cpu_reg_dump
ret
endfunc cortex_a57_cpu_reg_dump
declare_cpu_ops cortex_a57, CORTEX_A57_MIDR, \
declare_cpu_ops_workaround_cve_2017_5715 cortex_a57, CORTEX_A57_MIDR, \
cortex_a57_reset_func, \
check_errata_cve_2017_5715, \
cortex_a57_core_pwr_dwn, \
cortex_a57_cluster_pwr_dwn

4
lib/cpus/aarch64/cortex_a72.S
View File

@ -292,8 +292,8 @@ func cortex_a72_cpu_reg_dump
ret
endfunc cortex_a72_cpu_reg_dump
declare_cpu_ops cortex_a72, CORTEX_A72_MIDR, \
declare_cpu_ops_workaround_cve_2017_5715 cortex_a72, CORTEX_A72_MIDR, \
cortex_a72_reset_func, \
check_errata_cve_2017_5715, \
cortex_a72_core_pwr_dwn, \
cortex_a72_cluster_pwr_dwn

3
lib/cpus/aarch64/cortex_a73.S
View File

@ -170,7 +170,8 @@ func cortex_a73_cpu_reg_dump
ret
endfunc cortex_a73_cpu_reg_dump
declare_cpu_ops cortex_a73, CORTEX_A73_MIDR, \
declare_cpu_ops_workaround_cve_2017_5715 cortex_a73, CORTEX_A73_MIDR, \
cortex_a73_reset_func, \
check_errata_cve_2017_5715, \
cortex_a73_core_pwr_dwn, \
cortex_a73_cluster_pwr_dwn

3
lib/cpus/aarch64/cortex_a75.S
View File

@ -113,6 +113,7 @@ func cortex_a75_cpu_reg_dump
ret
endfunc cortex_a75_cpu_reg_dump
declare_cpu_ops cortex_a75, CORTEX_A75_MIDR, \
declare_cpu_ops_workaround_cve_2017_5715 cortex_a75, CORTEX_A75_MIDR, \
cortex_a75_reset_func, \
check_errata_cve_2017_5715, \
cortex_a75_core_pwr_dwn

37
lib/cpus/aarch64/cpu_helpers.S
View File

@ -1,5 +1,5 @@
/*
* Copyright (c) 2014-2017, ARM Limited and Contributors. All rights reserved.
* Copyright (c) 2014-2018, ARM Limited and Contributors. All rights reserved.
*
* SPDX-License-Identifier: BSD-3-Clause
*/
@ -7,9 +7,7 @@
#include <arch.h>
#include <asm_macros.S>
#include <assert_macros.S>
#if defined(IMAGE_BL31) || (defined(IMAGE_BL2) && BL2_AT_EL3)
#include <cpu_data.h>
#endif
#include <cpu_macros.S>
#include <debug.h>
#include <errata_report.h>
@ -281,3 +279,36 @@ func print_errata_status
br x1
endfunc print_errata_status
#endif
/*
* int check_workaround_cve_2017_5715(void);
*
* This function returns:
* - ERRATA_APPLIES when firmware mitigation is required.
* - ERRATA_NOT_APPLIES when firmware mitigation is _not_ required.
* - ERRATA_MISSING when firmware mitigation would be required but
* is not compiled in.
*
* NOTE: Must be called only after cpu_ops have been initialized
* in per-CPU data.
*/
.globl check_workaround_cve_2017_5715
func check_workaround_cve_2017_5715
mrs x0, tpidr_el3
#if ENABLE_ASSERTIONS
cmp x0, #0
ASM_ASSERT(ne)
#endif
ldr x0, [x0, #CPU_DATA_CPU_OPS_PTR]
ldr x0, [x0, #CPU_EXTRA1_FUNC]
/*
* If the reserved function pointer is NULL, this CPU
* is unaffected by CVE-2017-5715 so bail out.
*/
cmp x0, #0
beq 1f
br x0
1:
mov x0, #ERRATA_NOT_APPLIES
ret
endfunc check_workaround_cve_2017_5715

13
services/arm_arch_svc/arm_arch_svc_setup.c
View File

@ -6,9 +6,11 @@
#include <arm_arch_svc.h>
#include <debug.h>
#include <errata_report.h>
#include <runtime_svc.h>
#include <smcc.h>
#include <smcc_helpers.h>
#include <workaround_cve_2017_5715.h>
static int32_t smccc_version(void)
{
@ -17,14 +19,19 @@ static int32_t smccc_version(void)
static int32_t smccc_arch_features(u_register_t arg)
{
int ret;
switch (arg) {
case SMCCC_VERSION:
case SMCCC_ARCH_FEATURES:
return SMC_OK;
#if WORKAROUND_CVE_2017_5715
case SMCCC_ARCH_WORKAROUND_1:
return SMC_OK;
#endif
ret = check_workaround_cve_2017_5715();
if (ret == ERRATA_APPLIES)
return 0;
else if (ret == ERRATA_NOT_APPLIES)
return 1;
return -1; /* ERRATA_MISSING */
default:
return SMC_UNK;
}