From: Dave Hansen <dave.hansen@intel.com>
To: ira.weiny@intel.com, Jarkko Sakkinen <jarkko@kernel.org>
Cc: Sean Christopherson <seanjc@google.com>,
Jethro Beekman <jethro@fortanix.com>,
linux-kernel@vger.kernel.org, linux-sgx@vger.kernel.org
Subject: Re: [PATCH v4] x86: Remove unnecessary kmap() from sgx_ioc_enclave_init()
Date: Fri, 5 Feb 2021 09:03:16 -0800 [thread overview]
Message-ID: <9aa7a285-d620-f623-54ec-cbdedcbf7377@intel.com> (raw)
In-Reply-To: <20210205170030.856723-1-ira.weiny@intel.com>
On 2/5/21 9:00 AM, ira.weiny@intel.com wrote:
> From: Ira Weiny <ira.weiny@intel.com>
>
> kmap is inefficient and we are trying to reduce the usage in the kernel.
> There is no readily apparent reason why initp_page needs to be allocated
> and kmap'ed() but sigstruct needs to be page aligned and token
> 512 byte aligned.
>
> kmalloc() can give us this alignment but we need to allocate PAGE_SIZE
> bytes to do so. Rather than change this kmap() to kmap_local_page() use
> kmalloc() instead.
>
> Remove the alloc_page()/kmap() and replace with kmalloc(PAGE_SIZE, ...)
> to get a page aligned kernel address to use.
>
> In addition add a comment to document the alignment requirements so that
> others like myself don't attempt to 'fix' this again.
Looks good:
Acked-by: Dave Hansen <dave.hansen@intel.com>
next prev parent reply other threads:[~2021-02-05 19:47 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-02-05 17:00 [PATCH v4] x86: Remove unnecessary kmap() from sgx_ioc_enclave_init() ira.weiny
2021-02-05 17:03 ` Dave Hansen [this message]
2021-02-07 21:17 ` Jarkko Sakkinen
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