On Tue, Mar 31, 2020 at 08:53:07PM -0300, Thiago Jung Bauermann wrote:

Hi Ram,

Ram Pai [off-list ref] writes:

quoted

diff --git a/arch/powerpc/sysdev/xive/spapr.c b/arch/powerpc/sysdev/xive/spapr.c
index 55dc61c..608b52f 100644
--- a/arch/powerpc/sysdev/xive/spapr.c
+++ b/arch/powerpc/sysdev/xive/spapr.c

@@ -26,6 +26,8 @@
 #include <asm/xive.h>
 #include <asm/xive-regs.h>
 #include <asm/hvcall.h>
+#include <asm/svm.h>
+#include <asm/ultravisor.h>
 
 #include "xive-internal.h"
 

@@ -501,6 +503,9 @@ static int xive_spapr_configure_queue(u32 target, struct xive_q *q, u8 prio,
 		rc = -EIO;
 	} else {
 		q->qpage = qpage;
+		if (is_secure_guest())
+			uv_share_page(PHYS_PFN(qpage_phys),
+					1 << xive_alloc_order(order));

If I understand this correctly, you're passing the number of bytes of
the queue to uv_share_page(), but that ultracall expects the number of
pages to be shared.

static inline u32 xive_alloc_order(u32 queue_shift)
{
        return (queue_shift > PAGE_SHIFT) ? (queue_shift - PAGE_SHIFT) : 0;
}

xive_alloc_order(order) returns the order of PAGE_SIZE pages.
Hence the value passed to uv_shared_pages is the number of pages,
and not the number of bytes.

BTW: I did verify through testing that it was indeed passing 1 page to the
uv_share_page().  

RP