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Date:   Tue, 17 Jan 2023 16:26:13 +0530
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Subject: Re: [bug report] x86/hyperv: Add Write/Read MSR registers via ghcb
 page
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To:     Dan Carpenter <error27@gmail.com>, Tianyu.Lan@microsoft.com
Cc:     linux-hyperv@vger.kernel.org
References: <Y8UM59rdoCD0D6V2@kili>
From:   Jinank Jain <jinankjain@linux.microsoft.com>
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Does making 0 as the default value makes sense?

Regards,

Jinank

On 1/16/2023 2:07 PM, Dan Carpenter wrote:
> Hello Tianyu Lan,
>
> The patch faff44069ff5: "x86/hyperv: Add Write/Read MSR registers via
> ghcb page" from Oct 25, 2021, leads to the following Smatch static
> checker warning:
>
> 	arch/x86/kernel/cpu/mshyperv.c:73 hv_get_non_nested_register()
> 	error: uninitialized symbol 'value'.
>
> arch/x86/kernel/cpu/mshyperv.c
>      63
>      64 #if IS_ENABLED(CONFIG_HYPERV)
>      65 u64 hv_get_non_nested_register(unsigned int reg)
>      66 {
>      67         u64 value;
>      68
>      69         if (hv_is_synic_reg(reg) && hv_isolation_type_snp())
>      70                 hv_ghcb_msr_read(reg, &value);
>                                               ^^^^^^
> There are three places in hv_ghcb_msr_read() which don't initialize
> value.
>
>      71         else
>      72                 rdmsrl(reg, value);
> --> 73         return value;
>      74 }
>
> regards,
> dan carpenter