[Xen-changelog] [qemu-xen master] ppc/pnv: Fix fatal bug on 32-bit hosts

[patchbot@xxxxxxx]

commit 27d9ffd4b3718707c302fc0aad4746b958443c3a
Author:     David Gibson <david@xxxxxxxxxxxxxxxxxxxxx>
AuthorDate: Mon Nov 14 10:12:57 2016 +0100
Commit:     David Gibson <david@xxxxxxxxxxxxxxxxxxxxx>
CommitDate: Tue Nov 15 10:08:43 2016 +1100

    ppc/pnv: Fix fatal bug on 32-bit hosts
    
    If the pnv machine type is compiled on a 32-bit host, the unsigned long
    (host) type is 32-bit.  This means that the hweight_long() used to
    calculate the number of allowed cores only considers the low 32 bits of
    the cores_mask variable, and can thus return 0 in some circumstances.
    
    This corrects the bug.
    
    Signed-off-by: David Gibson <david@xxxxxxxxxxxxxxxxxxxxx>
    Suggested-by: Richard Henderson <rth@xxxxxxxxxxx>
    [clg: replaced hweight_long() by ctpop64() ]
    Signed-off-by: Cédric Le Goater <clg@xxxxxxxx>
    Signed-off-by: David Gibson <david@xxxxxxxxxxxxxxxxxxxxx>
---
 hw/ppc/pnv.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/hw/ppc/pnv.c b/hw/ppc/pnv.c
index e777958..9df7b25 100644
--- a/hw/ppc/pnv.c
+++ b/hw/ppc/pnv.c
@@ -620,7 +620,7 @@ static void pnv_chip_core_sanitize(PnvChip *chip, Error 
**errp)
     chip->cores_mask &= pcc->cores_mask;
 
     /* now that we have a sane layout, let check the number of cores */
-    cores_max = hweight_long(chip->cores_mask);
+    cores_max = ctpop64(chip->cores_mask);
     if (chip->nr_cores > cores_max) {
         error_setg(errp, "warning: too many cores for chip ! Limit is %d",
                    cores_max);
--
generated by git-patchbot for /home/xen/git/qemu-xen.git#master

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