+ Phil
Hi Ira,
On Sun, 2 Oct 2022 at 05:53, ira.weiny@intel.com wrote:
From: Ira Weiny ira.weiny@intel.com
The kernel pages used by shm_get_kernel_pages() are allocated using GFP_KERNEL through the following call stack:
trusted_instantiate() trusted_payload_alloc() -> GFP_KERNEL <trusted key op> tee_shm_register_kernel_buf() register_shm_helper() shm_get_kernel_pages()
Where <trusted key op> is one of:
trusted_key_unseal() trusted_key_get_random() trusted_key_seal()
Remove the vmalloc page support from shm_get_kernel_pages(). Replace with a warn on once.
Cc: Jens Wiklander jens.wiklander@linaro.org Cc: Al Viro viro@zeniv.linux.org.uk Cc: "Fabio M. De Francesco" fmdefrancesco@gmail.com Cc: Christoph Hellwig hch@lst.de Cc: Linus Torvalds torvalds@linux-foundation.org Signed-off-by: Ira Weiny ira.weiny@intel.com
Jens I went with the suggestion from Linus and Christoph and rejected vmalloc addresses. I did not hear back from you regarding Linus' question if the vmalloc page support was required by an up coming patch set or not. So I assumed it was something out of tree.
It looks like I wasn't CC'd to that conversation. IIRC, support for vmalloc addresses was added recently by Phil here [1]. So I would like to give him a chance if he is planning to post a corresponding kernel driver upstream.
[1] https://lists.trustedfirmware.org/archives/list/op-tee@lists.trustedfirmware...
-Sumit
drivers/tee/tee_shm.c | 36 ++++++++++++------------------------ 1 file changed, 12 insertions(+), 24 deletions(-)
diff --git a/drivers/tee/tee_shm.c b/drivers/tee/tee_shm.c index 27295bda3e0b..527a6eabc03e 100644 --- a/drivers/tee/tee_shm.c +++ b/drivers/tee/tee_shm.c @@ -24,37 +24,25 @@ static void shm_put_kernel_pages(struct page **pages, size_t page_count) static int shm_get_kernel_pages(unsigned long start, size_t page_count, struct page **pages) {
struct kvec *kiov; size_t n; int rc;
if (is_vmalloc_addr((void *)start)) {
struct page *page;
for (n = 0; n < page_count; n++) {
page = vmalloc_to_page((void *)(start + PAGE_SIZE * n));
if (!page)
return -ENOMEM;
get_page(page);
pages[n] = page;
}
rc = page_count;
} else {
struct kvec *kiov;
kiov = kcalloc(page_count, sizeof(*kiov), GFP_KERNEL);
if (!kiov)
return -ENOMEM;
if (WARN_ON_ONCE(is_vmalloc_addr((void *)start)))
return -EINVAL;
for (n = 0; n < page_count; n++) {
kiov[n].iov_base = (void *)(start + n * PAGE_SIZE);
kiov[n].iov_len = PAGE_SIZE;
}
kiov = kcalloc(page_count, sizeof(*kiov), GFP_KERNEL);
if (!kiov)
return -ENOMEM;
rc = get_kernel_pages(kiov, page_count, 0, pages);
kfree(kiov);
for (n = 0; n < page_count; n++) {
kiov[n].iov_base = (void *)(start + n * PAGE_SIZE);
kiov[n].iov_len = PAGE_SIZE; }
rc = get_kernel_pages(kiov, page_count, 0, pages);
kfree(kiov);
return rc;
}
-- 2.37.2