diff options
| author | Joel Sing <jsing@cvs.openbsd.org> | 2014-02-18 13:47:54 +0000 |
|---|---|---|
| committer | Joel Sing <jsing@cvs.openbsd.org> | 2014-02-18 13:47:54 +0000 |
| commit | cb25d9dbac4029fd7ef13c8ebb998bf9de079b72 (patch) | |
| tree | b5a05595ef92b7cc6fd46098ff3390c4622f4493 /sys/arch/amd64 | |
| parent | 5217c20a82ac161e88a3b8bca3e57deaba75acaa (diff) | |
Actually check to see if the CPU supports tsc, rather than assuming that
it does and triggering an illegal instruction trap when it does not.
Found the hard way and fix tested by nick@
Diffstat (limited to 'sys/arch/amd64')
| -rw-r--r-- | sys/arch/amd64/stand/libsa/random_i386.S | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/sys/arch/amd64/stand/libsa/random_i386.S b/sys/arch/amd64/stand/libsa/random_i386.S index 987c0a25fca..dc94f373449 100644 --- a/sys/arch/amd64/stand/libsa/random_i386.S +++ b/sys/arch/amd64/stand/libsa/random_i386.S @@ -55,6 +55,7 @@ ENTRY(mdrandom) movl $1, %eax movl $0, %ecx cpuid + movl %edx, %eax movl 36(%esp), %ebx movl 40(%esp), %edx @@ -65,7 +66,10 @@ ENTRY(mdrandom) jnz userand movl %edx, %ecx - jmp usetsc + andl $CPUID_TSC, %eax // See if we have rdtsc. + jnz usetsc + + jmp done userand: rdrand %eax |