powerpc/64s: Enhance the information in cpu_show_meltdown()

Now that we have the security feature flags we can make the
information displayed in the "meltdown" file more informative.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This commit is contained in:
Michael Ellerman 2018-03-27 23:01:49 +11:00
parent 8ad3304156
commit ff348355e9
2 changed files with 29 additions and 2 deletions

View File

@ -10,6 +10,7 @@
extern unsigned long powerpc_security_features;
extern bool rfi_flush;
static inline void security_ftr_set(unsigned long feature)
{

View File

@ -6,6 +6,7 @@
#include <linux/kernel.h>
#include <linux/device.h>
#include <linux/seq_buf.h>
#include <asm/security_features.h>
@ -19,8 +20,33 @@ unsigned long powerpc_security_features __read_mostly = \
ssize_t cpu_show_meltdown(struct device *dev, struct device_attribute *attr, char *buf)
{
if (rfi_flush)
return sprintf(buf, "Mitigation: RFI Flush\n");
bool thread_priv;
thread_priv = security_ftr_enabled(SEC_FTR_L1D_THREAD_PRIV);
if (rfi_flush || thread_priv) {
struct seq_buf s;
seq_buf_init(&s, buf, PAGE_SIZE - 1);
seq_buf_printf(&s, "Mitigation: ");
if (rfi_flush)
seq_buf_printf(&s, "RFI Flush");
if (rfi_flush && thread_priv)
seq_buf_printf(&s, ", ");
if (thread_priv)
seq_buf_printf(&s, "L1D private per thread");
seq_buf_printf(&s, "\n");
return s.len;
}
if (!security_ftr_enabled(SEC_FTR_L1D_FLUSH_HV) &&
!security_ftr_enabled(SEC_FTR_L1D_FLUSH_PR))
return sprintf(buf, "Not affected\n");
return sprintf(buf, "Vulnerable\n");
}