3f9c958e35
commit b9baf5c8c5c356757f4f9d8180b5e9d234065bc3 upstream. Workaround the Spectre BHB issues for Cortex-A15, Cortex-A57, Cortex-A72, Cortex-A73 and Cortex-A75. We also include Brahma B15 as well to be safe, which is affected by Spectre V2 in the same ways as Cortex-A15. Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> [changes due to lack of SYSTEM_FREEING_INITMEM - gregkh] Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
59 lines
1.3 KiB
C
59 lines
1.3 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
|
|
#include <linux/cpu.h>
|
|
#include <linux/device.h>
|
|
|
|
#include <asm/spectre.h>
|
|
|
|
ssize_t cpu_show_spectre_v1(struct device *dev, struct device_attribute *attr,
|
|
char *buf)
|
|
{
|
|
return sprintf(buf, "Mitigation: __user pointer sanitization\n");
|
|
}
|
|
|
|
static unsigned int spectre_v2_state;
|
|
static unsigned int spectre_v2_methods;
|
|
|
|
void spectre_v2_update_state(unsigned int state, unsigned int method)
|
|
{
|
|
if (state > spectre_v2_state)
|
|
spectre_v2_state = state;
|
|
spectre_v2_methods |= method;
|
|
}
|
|
|
|
ssize_t cpu_show_spectre_v2(struct device *dev, struct device_attribute *attr,
|
|
char *buf)
|
|
{
|
|
const char *method;
|
|
|
|
if (spectre_v2_state == SPECTRE_UNAFFECTED)
|
|
return sprintf(buf, "%s\n", "Not affected");
|
|
|
|
if (spectre_v2_state != SPECTRE_MITIGATED)
|
|
return sprintf(buf, "%s\n", "Vulnerable");
|
|
|
|
switch (spectre_v2_methods) {
|
|
case SPECTRE_V2_METHOD_BPIALL:
|
|
method = "Branch predictor hardening";
|
|
break;
|
|
|
|
case SPECTRE_V2_METHOD_ICIALLU:
|
|
method = "I-cache invalidation";
|
|
break;
|
|
|
|
case SPECTRE_V2_METHOD_SMC:
|
|
case SPECTRE_V2_METHOD_HVC:
|
|
method = "Firmware call";
|
|
break;
|
|
|
|
case SPECTRE_V2_METHOD_LOOP8:
|
|
method = "History overwrite";
|
|
break;
|
|
|
|
default:
|
|
method = "Multiple mitigations";
|
|
break;
|
|
}
|
|
|
|
return sprintf(buf, "Mitigation: %s\n", method);
|
|
}
|