| Message ID | 20210224222049.240754-1-jarkko@kernel.org (mailing list archive) |
|---|---|
| Headers | show |
| Series | Introduce version array structure: sgx_va | expand |
On 2/24/21 2:20 PM, Jarkko Sakkinen wrote: > The use of sgx_va can be later on extended to the following use cases: > > - A global VA for reclaimed SECS pages. > - A global VA for reclaimed VA pages. ... > arch/x86/kernel/cpu/sgx/driver.c | 3 +- > arch/x86/kernel/cpu/sgx/encl.c | 180 ++++++++++++++++++++++--------- > arch/x86/kernel/cpu/sgx/encl.h | 36 ++++--- > arch/x86/kernel/cpu/sgx/ioctl.c | 77 +++++-------- > arch/x86/kernel/cpu/sgx/main.c | 19 +--- > 5 files changed, 184 insertions(+), 131 deletions(-) It looks interesting. Were you planning on keeping this on the back burner until we need it more acutely? Or, were you thinking it should be merged immediately?
On Wed, Feb 24, 2021 at 03:48:50PM -0800, Dave Hansen wrote: > On 2/24/21 2:20 PM, Jarkko Sakkinen wrote: > > The use of sgx_va can be later on extended to the following use cases: > > > > - A global VA for reclaimed SECS pages. > > - A global VA for reclaimed VA pages. > ... > > arch/x86/kernel/cpu/sgx/driver.c | 3 +- > > arch/x86/kernel/cpu/sgx/encl.c | 180 ++++++++++++++++++++++--------- > > arch/x86/kernel/cpu/sgx/encl.h | 36 ++++--- > > arch/x86/kernel/cpu/sgx/ioctl.c | 77 +++++-------- > > arch/x86/kernel/cpu/sgx/main.c | 19 +--- > > 5 files changed, 184 insertions(+), 131 deletions(-) > > It looks interesting. > > Were you planning on keeping this on the back burner until we need it > more acutely? Or, were you thinking it should be merged immediately? I think this can wait. Perhaps, this could be picked to some other patch set, such as EDMM. Let's just say that this should be part of anything that touches the page reclaimer. IDA might look odd. Mapping through IDA allocated ID's is for conserving the amount of used EPC pages for the version array. Alternative would be to linearly map enclave page offset to the VA page index but that would introduce a sloppy allocation of EPC. The selected approach, on the other hand, no matter how sparsely you create enclave pages, that does not add to the amount of EPC VA page usage. BTW, encl_page->va_page could be removed, and use sgx_va_get() to locate the VA page, when needed. I'm open for opinions with this one: it's space vs the cost of access question. /Jarkko
On Thu, Feb 25, 2021 at 12:20:46AM +0200, Jarkko Sakkinen wrote: > Introduce an xarray based version array (VA) structure: struct sgx_va. > > The use of sgx_va can be later on extended to the following use cases: > > - A global VA for reclaimed SECS pages. > - A global VA for reclaimed VA pages. > > Testing done while developing the patch: > > - With NUC7PJYH: https://www.intel.com/content/www/us/en/products/boards-kits/nuc/kits/nuc7pjyh.html > - seq 10000 | xargs -I {} -P10000 ./test_sgx > /dev/null > - The EPC size was set from BIOS to 32 MB. In [1], 'va' branch is tip/master with the patch set on top. [1] https://git.kernel.org/pub/scm/linux/kernel/git/jarkko/linux-sgx.git: /Jarkko
Introduce an xarray based version array (VA) structure: struct sgx_va. The use of sgx_va can be later on extended to the following use cases: - A global VA for reclaimed SECS pages. - A global VA for reclaimed VA pages. Testing done while developing the patch: - With NUC7PJYH: https://www.intel.com/content/www/us/en/products/boards-kits/nuc/kits/nuc7pjyh.html - seq 10000 | xargs -I {} -P10000 ./test_sgx > /dev/null - The EPC size was set from BIOS to 32 MB. Jarkko Sakkinen (3): x86/sgx: Move struct sgx_va_page creation to sgx_alloc_va_page() x86/sgx: Add a version array (VA) structure x86/sgx: Use sgx_va for the enclave's version array arch/x86/kernel/cpu/sgx/driver.c | 3 +- arch/x86/kernel/cpu/sgx/encl.c | 180 ++++++++++++++++++++++--------- arch/x86/kernel/cpu/sgx/encl.h | 36 ++++--- arch/x86/kernel/cpu/sgx/ioctl.c | 77 +++++-------- arch/x86/kernel/cpu/sgx/main.c | 19 +--- 5 files changed, 184 insertions(+), 131 deletions(-)