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Date:   Thu, 11 Aug 2022 22:58:16 +0530
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Subject: Re: [PATCH v7 00/14] KVM: mm: fd-based approach for supporting KVM
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To:     Chao Peng <chao.p.peng@linux.intel.com>,
        "Gupta, Pankaj" <pankaj.gupta@amd.com>
Cc:     Sean Christopherson <seanjc@google.com>,
        Paolo Bonzini <pbonzini@redhat.com>,
        Jonathan Corbet <corbet@lwn.net>,
        Vitaly Kuznetsov <vkuznets@redhat.com>,
        Wanpeng Li <wanpengli@tencent.com>,
        Jim Mattson <jmattson@google.com>,
        Joerg Roedel <joro@8bytes.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        x86@kernel.org, "H . Peter Anvin" <hpa@zytor.com>,
        Hugh Dickins <hughd@google.com>,
        Jeff Layton <jlayton@kernel.org>,
        "J . Bruce Fields" <bfields@fieldses.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Shuah Khan <shuah@kernel.org>, Mike Rapoport <rppt@kernel.org>,
        Steven Price <steven.price@arm.com>,
        "Maciej S . Szmigiero" <mail@maciej.szmigiero.name>,
        Vlastimil Babka <vbabka@suse.cz>,
        Vishal Annapurve <vannapurve@google.com>,
        Yu Zhang <yu.c.zhang@linux.intel.com>,
        "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>,
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        Quentin Perret <qperret@google.com>,
        Michael Roth <michael.roth@amd.com>, mhocko@suse.com,
        Muchun Song <songmuchun@bytedance.com>, bharata@amd.com,
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From:   "Nikunj A. Dadhania" <nikunj@amd.com>
In-Reply-To: <20220811133255.GB916119@chaop.bj.intel.com>
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On 11/08/22 19:02, Chao Peng wrote:
> On Thu, Aug 11, 2022 at 01:30:06PM +0200, Gupta, Pankaj wrote:
>>

>>>> Test
>>>> ----
>>>> To test the new functionalities of this patch TDX patchset is needed.
>>>> Since TDX patchset has not been merged so I did two kinds of test:
>>>>
>>>> -  Regresion test on kvm/queue (this patchset)
>>>>     Most new code are not covered. Code also in below repo:
>>>>     https://github.com/chao-p/linux/tree/privmem-v7
>>>>
>>>> -  New Funational test on latest TDX code
>>>>     The patch is rebased to latest TDX code and tested the new
>>>>     funcationalities. See below repos:
>>>>     Linux: https://github.com/chao-p/linux/tree/privmem-v7-tdx
>>>>     QEMU: https://github.com/chao-p/qemu/tree/privmem-v7
>>>
>>> While debugging an issue with SEV+UPM, found that fallocate() returns
>>> an error in QEMU which is not handled (EINTR). With the below handling
>>> of EINTR subsequent fallocate() succeeds:
> 
> QEMU code has not well-tested so it's not strange you met problem. But
> from the man page, there is signal was caught for EINTR, do you know
> the signal number?

I haven't check that, but that should be fairly straight forward to get.
I presume that you are referring to signal_pending() in the shmem_fallocate()

> Thanks for you patch but before we change it in QEMU I want to make sure
> it's indeed a QEMU issue (e.g. not a kernel isssue).

As per the manual fallocate() can return EINTR, and this should be handled 
by the user space.

Regards
Nikunj