powerpc/pseries: Avoid hcall in plpks_is_available() on non-pseries

plpks_is_available() can be called on any platform via kexec but calls
_plpks_get_config() which makes a hcall, which will only work on pseries.
Fix this by returning early in plpks_is_available() if hcalls aren't
possible.

Fixes: 119da30d037d ("powerpc/pseries: Expose PLPKS config values, support additional fields")
Reported-by: Murphy Zhou <[email protected]>
Signed-off-by: Russell Currey <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

diff --git a/arch/powerpc/platforms/pseries/plpks.c b/arch/powerpc/platforms/pseries/plpks.c
index cdf09e5bd74121d1ea09ce02f34e12fda203789c..6f7bf3fc3aea46fe475af765d2e21abb989be86c 100644 (file)
--- a/arch/powerpc/platforms/pseries/plpks.c
+++ b/arch/powerpc/platforms/pseries/plpks.c
@@ -22,6 +22,7 @@
 #include <asm/hvcall.h>
 #include <asm/machdep.h>
 #include <asm/plpks.h>
+#include <asm/firmware.h>
 
 static u8 *ospassword;
 static u16 ospasswordlength;
@@ -377,6 +378,9 @@ bool plpks_is_available(void)
 {
        int rc;
 
+       if (!firmware_has_feature(FW_FEATURE_LPAR))
+               return false;
+
        rc = _plpks_get_config();
        if (rc)
                return false;