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x86/sgx: Fix minor documentation issues

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The SGX documentation has a few repeated or one-off issues:

 * Remove capitalization from regular words in the middle of a sentence.
 * Remove punctuation found in the middle of a sentence.
 * Fix name of SGX daemon to consistently be ksgxd.
 * Fix typo of SGX instruction: ENIT -> EINIT

[ dhansen: tweaked subject and changelog ]

Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Link: https://lkml.kernel.org/r/ab99a87368eef69e3fb96f073368becff3eff874.1635529506.git.reinette.chatre@intel.com
This commit is contained in:
Reinette Chatre 2021-10-29 10:49:56 -07:00 committed by Dave Hansen
parent 688542e29f
commit 379e4de9e1
1 changed files with 7 additions and 7 deletions
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14
Documentation/x86/sgx.rst
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@ -10,7 +10,7 @@ Overview
Software Guard eXtensions (SGX) hardware enables for user space applications
to set aside private memory regions of code and data:
* Privileged (ring-0) ENCLS functions orchestrate the construction of the.
* Privileged (ring-0) ENCLS functions orchestrate the construction of the
regions.
* Unprivileged (ring-3) ENCLU functions allow an application to enter and
execute inside the regions.
@ -91,7 +91,7 @@ In addition to the traditional compiler and linker build process, SGX has a
separate enclave “build” process. Enclaves must be built before they can be
executed (entered). The first step in building an enclave is opening the
**/dev/sgx_enclave** device. Since enclave memory is protected from direct
access, special privileged instructions are Then used to copy data into enclave
access, special privileged instructions are then used to copy data into enclave
pages and establish enclave page permissions.
.. kernel-doc:: arch/x86/kernel/cpu/sgx/ioctl.c
@ -126,13 +126,13 @@ the need to juggle signal handlers.
ksgxd
=====
SGX support includes a kernel thread called *ksgxwapd*.
SGX support includes a kernel thread called *ksgxd*.
EPC sanitization
----------------
ksgxd is started when SGX initializes. Enclave memory is typically ready
For use when the processor powers on or resets. However, if SGX has been in
for use when the processor powers on or resets. However, if SGX has been in
use since the reset, enclave pages may be in an inconsistent state. This might
occur after a crash and kexec() cycle, for instance. At boot, ksgxd
reinitializes all enclave pages so that they can be allocated and re-used.
@ -147,7 +147,7 @@ Page reclaimer
Similar to the core kswapd, ksgxd, is responsible for managing the
overcommitment of enclave memory. If the system runs out of enclave memory,
*ksgxwapd* “swaps” enclave memory to normal memory.
*ksgxd* “swaps” enclave memory to normal memory.
Launch Control
==============
@ -156,7 +156,7 @@ SGX provides a launch control mechanism. After all enclave pages have been
copied, kernel executes EINIT function, which initializes the enclave. Only after
this the CPU can execute inside the enclave.
ENIT function takes an RSA-3072 signature of the enclave measurement. The function
EINIT function takes an RSA-3072 signature of the enclave measurement. The function
checks that the measurement is correct and signature is signed with the key
hashed to the four **IA32_SGXLEPUBKEYHASH{0, 1, 2, 3}** MSRs representing the
SHA256 of a public key.
@ -184,7 +184,7 @@ CPUs starting from Icelake use Total Memory Encryption (TME) in the place of
MEE. TME-based SGX implementations do not have an integrity Merkle tree, which
means integrity and replay-attacks are not mitigated. B, it includes
additional changes to prevent cipher text from being returned and SW memory
aliases from being Created.
aliases from being created.
DMA to enclave memory is blocked by range registers on both MEE and TME systems
(SDM section 41.10).