Re: [Qemu-devel] [PATCH 2/3 V3] s390: implement pci instructions

[Cornelia Huck]

On Tue, 20 Jan 2015 10:45:41 +0100
Markus Armbruster <address@hidden> wrote:

> This patch makes Coverity unhappy:
> 
> *** CID 1264326:  Unintended sign extension  (SIGN_EXTENSION)
> /hw/s390x/s390-pci-inst.c: 787 in stpcifc_service_call()
> 781         stq_p(&fib.pal, pbdev->pal);
> 782         stq_p(&fib.iota, pbdev->g_iota);
> 783         stq_p(&fib.aibv, pbdev->routes.adapter.ind_addr);
> 784         stq_p(&fib.aisb, pbdev->routes.adapter.summary_addr);
> 785         stq_p(&fib.fmb_addr, pbdev->fmb_addr);
> 786     
> >>>     CID 1264326:  Unintended sign extension  (SIGN_EXTENSION)
> >>>     Suspicious implicit sign extension: "pbdev->isc" with type
> >>> "unsigned char" (8 bits, unsigned) is promoted in "(pbdev->isc <<
> >>> 28) | (pbdev->noi << 16)" to type "int" (32 bits, signed), then
> >>> sign-extended to type "unsigned long" (64 bits, unsigned).  If
> >>> "(pbdev->isc << 28) | (pbdev->noi << 16)" is greater than
> >>> 0x7FFFFFFF, the upper bits of the result will all be 1.
> 787         data = (pbdev->isc << 28) | (pbdev->noi << 16) |
> 788                (pbdev->routes.adapter.ind_offset << 8) | (pbdev->sum << 
> 7) |
> 789                pbdev->routes.adapter.summary_offset;
> 790         stw_p(&fib.data, data);
> 791     
> 792         if (pbdev->fh >> ENABLE_BIT_OFFSET) {

There's a fix for this (and the memory leak):

http://marc.info/?l=qemu-devel&m=142124886620078&w=2

The patch is sitting in my queue, will send with the next pile of s390x
updates.