Jon Doron af510d6fd6 x86/kvm/hyper-v: Explicitly align hcall param for kvm_hyperv_exit ... [ Upstream commit f7d31e6536 ] The problem the patch is trying to address is the fact that 'struct kvm_hyperv_exit' has different layout on when compiling in 32 and 64 bit modes. In 64-bit mode the default alignment boundary is 64 bits thus forcing extra gaps after 'type' and 'msr' but in 32-bit mode the boundary is at 32 bits thus no extra gaps. This is an issue as even when the kernel is 64 bit, the userspace using the interface can be both 32 and 64 bit but the same 32 bit userspace has to work with 32 bit kernel. The issue is fixed by forcing the 64 bit layout, this leads to ABI change for 32 bit builds and while we are obviously breaking '32 bit userspace with 32 bit kernel' case, we're fixing the '32 bit userspace with 64 bit kernel' one. As the interface has no (known) users and 32 bit KVM is rather baroque nowadays, this seems like a reasonable decision. Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: Jon Doron <arilou@gmail.com> Message-Id: <20200424113746.3473563-2-arilou@gmail.com> Reviewed-by: Roman Kagan <rvkagan@yandex-team.ru> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>		2020-06-22 09:30:57 +02:00
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kvm	x86/kvm/hyper-v: Explicitly align hcall param for kvm_hyperv_exit	2020-06-22 09:30:57 +02:00
uml	Documentation: move Documentation/virtual to Documentation/virt	2019-07-24 10:52:11 +02:00
index.rst	Documentation: move Documentation/virtual to Documentation/virt	2019-07-24 10:52:11 +02:00
paravirt_ops.rst	Documentation: move Documentation/virtual to Documentation/virt	2019-07-24 10:52:11 +02:00