From: Don Slutz <dslutz@verizon.com>
To: Eric Blake <eblake@redhat.com>,
"qemu-devel@nongnu.org" <qemu-devel@nongnu.org>
Cc: "Michael S. Tsirkin" <mst@redhat.com>,
"Markus Armbruster" <armbru@redhat.com>,
"Luiz Capitulino" <lcapitulino@redhat.com>,
"Don Slutz" <don.slutz@gmail.com>,
"Anthony Liguori" <aliguori@amazon.com>,
"Paolo Bonzini" <pbonzini@redhat.com>,
"Andreas Färber" <afaerber@suse.de>,
"Richard Henderson" <rth@twiddle.net>
Subject: Re: [Qemu-devel] [BUGFIX][PATCH v7 1/9] vmport: The io memory region needs to be at least a size of 4
Date: Mon, 15 Jun 2015 09:53:23 -0400 [thread overview]
Message-ID: <557ED8D3.8010900@one.verizon.com> (raw)
In-Reply-To: <557B5F49.5050109@redhat.com>
On 06/12/15 18:38, Eric Blake wrote:
> On 06/12/2015 08:05 AM, Don Slutz wrote:
>> Before:
>>
>> commit c3c1bb99d1c11978d9ce94d1bdcf0705378c1459
>> Author: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
>> Date: Mon Mar 16 22:35:54 2015 -0700
>>
>> exec: Respect as_tranlsate_internal length clamp
>>
>> it did not matter. Only accept I/O that starts on 1st
>> port.
>>
>> Signed-off-by: Don Slutz <dslutz@verizon.com>
>> CC: Don Slutz <don.slutz@gmail.com>
>> ---
>> hw/misc/vmport.c | 6 +++++-
>> 1 file changed, 5 insertions(+), 1 deletion(-)
>>
>> diff --git a/hw/misc/vmport.c b/hw/misc/vmport.c
>> index 7fcc00d..51b64bc 100644
>> --- a/hw/misc/vmport.c
>> +++ b/hw/misc/vmport.c
>> @@ -69,6 +69,10 @@ static uint64_t vmport_ioport_read(void *opaque, hwaddr addr,
>> unsigned char command;
>> uint32_t eax;
>>
>> + /* Only support 1 address */
>> + if (addr) {
>> + return ~0U;
>> + }
>
> Different answer on 32-bit platforms (there, ~0U is 0xffffffff, which
> then 0-extends to uint64_t rather than your desired result of
> 0xffffffffffffffffULL).
>
This is not true:
Using:
build1:~/tmp>cat zr64.c
#include <stdio.h>
#include <stdint.h>
uint64_t vmport_ioport_read(void)
{
return ~0U;
}
int
main(void)
{
uint64_t res = vmport_ioport_read();
printf("res=0x%llx\n", res);
}
On 32-bits:
build1:~/tmp>file zr64
zr64: ELF 32-bit LSB executable, Intel 80386, version 1 (SYSV),
dynamically linked (uses shared libs), for GNU/Linux 2.6.18, not stripped
build1:~/tmp>./zr64
res=0xffffffff
on 64-bits:
build2:~/tmp>file zr64
zr64: ELF 64-bit LSB executable, x86-64, version 1 (SYSV), dynamically
linked (uses shared libs), for GNU/Linux 2.6.18, not stripped
build2:~/tmp>./zr64
res=0xffffffff
> Why can't you just 'return -1;'?
>
I/O instructions on x86 are limited to 32bits max. Also when EAX is
changed via inl, the high 32bits are 0. So the correct result is ~0U
not -1.
-Don Slutz
next prev parent reply other threads:[~2015-06-15 13:53 UTC|newest]
Thread overview: 44+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-06-12 14:05 [Qemu-devel] [PATCH v7 0/9] Add limited support of VMware's hyper-call rpc Don Slutz
2015-06-12 14:05 ` [Qemu-devel] [BUGFIX][PATCH v7 1/9] vmport: The io memory region needs to be at least a size of 4 Don Slutz
2015-06-12 22:38 ` Eric Blake
2015-06-15 13:53 ` Don Slutz [this message]
2015-06-15 15:09 ` Eric Blake
2015-06-15 16:15 ` Don Slutz
2015-06-12 14:05 ` [Qemu-devel] [PATCH v7 2/9] vmport: Switch to trace Don Slutz
2015-06-12 14:05 ` [Qemu-devel] [BUGFIX][PATCH v7 3/9] vmport: Fix vmport_cmd_ram_size Don Slutz
2015-06-12 14:05 ` [Qemu-devel] [PATCH v7 4/9] vmport_rpc: Add the object vmport_rpc Don Slutz
2015-06-12 14:05 ` [Qemu-devel] [PATCH v7 5/9] vmport_rpc: Add limited support of VMware's hyper-call rpc Don Slutz
2015-06-12 14:05 ` [Qemu-devel] [PATCH v7 6/9] vmport_rpc: Add QMP access to vmport_rpc object Don Slutz
2015-06-15 15:53 ` Eric Blake
2015-06-17 16:42 ` Don Slutz
2015-06-12 14:05 ` [Qemu-devel] [PATCH v7 7/9] vmport_rpc: Add migration Don Slutz
2015-06-12 14:05 ` [Qemu-devel] [PATCH v7 8/9] vmport: Add VMware all ring hack Don Slutz
2015-06-12 14:05 ` [Qemu-devel] [PATCH v7 9/9] MAINTAINERS: add VMware port Don Slutz
2015-06-17 13:44 ` [Qemu-devel] [PATCH v7 0/9] Add limited support of VMware's hyper-call rpc Paolo Bonzini
2015-06-17 22:26 ` Don Slutz
2015-06-18 7:58 ` Michael S. Tsirkin
2015-06-18 8:33 ` Paolo Bonzini
2015-06-18 9:40 ` Michael S. Tsirkin
2015-06-18 8:33 ` Paolo Bonzini
2015-06-17 14:11 ` Michael S. Tsirkin
2015-06-17 14:13 ` Paolo Bonzini
2015-06-17 14:18 ` Michael S. Tsirkin
2015-06-17 14:27 ` Paolo Bonzini
2015-06-17 14:29 ` Michael S. Tsirkin
2015-06-17 16:17 ` Paolo Bonzini
2015-06-17 16:29 ` Michael S. Tsirkin
2015-06-17 16:48 ` Paolo Bonzini
2015-06-17 18:43 ` Michael S. Tsirkin
2015-06-17 19:15 ` Paolo Bonzini
2015-06-17 19:22 ` Michael S. Tsirkin
2015-06-17 19:24 ` Paolo Bonzini
2015-06-17 19:29 ` Michael S. Tsirkin
2015-06-17 17:03 ` Don Slutz
2015-06-17 17:14 ` Paolo Bonzini
2015-06-17 17:25 ` Paolo Bonzini
2015-06-17 17:34 ` Don Slutz
2015-06-17 18:58 ` Michael S. Tsirkin
2015-06-18 18:40 ` Don Slutz
2015-06-17 18:45 ` Michael S. Tsirkin
2015-06-17 18:45 ` Michael S. Tsirkin
2015-06-18 7:03 ` Gerd Hoffmann
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