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Re: [Qemu-devel] [qemu-s390x] [PATCH v2 1/3] hw/s390x/ipl: Fix alignment
Re: [Qemu-devel] [qemu-s390x] [PATCH v2 1/3] hw/s390x/ipl: Fix alignment problems of S390IPLState members
Wed, 26 Sep 2018 10:04:52 +0200
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On 2018-09-26 09:56, David Hildenbrand wrote:
> On 26/09/2018 09:38, Thomas Huth wrote:
>> The IplParameterBlock and QemuIplParameters structures are declared
>> with QEMU_PACKED, so the compiler assumes that the structures do not
>> need to be aligned in memory. Since the are listed after a "bool"
>> within the S390IPLState, the IplParameterBlock and QemuIplParameters
>> are also indeed mis-aligned in memory. This causes problems on Sparc
>> during migration, since we use VMSTATE_UINT16 in vmstate_iplb to access
>> the devno member for example, and the corresponding migration functions
>> (like qemu_get_be16s) then try to access a 16-bit value from a mis-
>> aligned memory address.
>> The easiest solution to fix this problem is to move the packed structures
>> to the beginning of the S390IPLState. Also add some additional comments
>> here to prevent that this problem will be introduced again in the future.
> The last sentence no longer applies.
Oops. Cornelia, could you please fix it up when picking up the patch (in
case there are no other reasons for respinning the series)?
[Qemu-devel] [PATCH v2 2/3] hw/s390x/css: Remove QEMU_PACKED from struct SenseId, Thomas Huth, 2018/09/26