lkml.org 
[lkml]   [2023]   [Jun]   [7]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
SubjectRe: [PATCH 4/9] drivers: hv: Mark shared pages unencrypted in SEV-SNP enlightened guest
From
On 6/5/2023 8:54 PM, Vitaly Kuznetsov wrote:
>> @@ -402,7 +417,14 @@ int hv_common_cpu_die(unsigned int cpu)
>>
>> local_irq_restore(flags);
>>
>> - kfree(mem);
>> + if (hv_isolation_type_en_snp()) {
>> + ret = set_memory_encrypted((unsigned long)mem, pgcount);
>> + if (ret)
>> + pr_warn("Hyper-V: Failed to encrypt input arg on cpu%d: %d\n",
>> + cpu, ret);
>> + /* It's unsafe to free 'mem'. */
>> + return 0;
> Why is it unsafe to free 'mem' if ret == 0? Also, why don't we want to
> proparate non-zero 'ret' from here to fail CPU offlining?
>

Based on Michael's patch the mem will not be freed during cpu offline.
https://lwn.net/ml/linux-kernel/87cz2j5zrc.fsf@redhat.com/
So I think it's unnessary to encrypt the mem again here.

\
 
 \ /
  Last update: 2023-06-07 10:17    [W:0.092 / U:1.760 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site