[PATCH v6 05/13] init: Call mem_encrypt_init() after Hyper-V hypercall init is done
From: Michael Kelley <hidden>
Date: 2023-03-09 02:42:13
Also in:
linux-arch, linux-hyperv, linux-iommu, linux-pci, lkml
Subsystem:
the rest · Maintainer:
Linus Torvalds
Full Hyper-V initialization, including support for hypercalls, is done as an apic_post_init callback via late_time_init(). mem_encrypt_init() needs to make hypercalls when it marks swiotlb memory as decrypted. But mem_encrypt_init() is currently called a few lines before late_time_init(), so the hypercalls don't work. Fix this by moving mem_encrypt_init() after late_time_init() and related clock initializations. The intervening initializations don't do any I/O that requires the swiotlb, so moving mem_encrypt_init() slightly later has no impact. Signed-off-by: Michael Kelley <redacted> Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com> --- init/main.c | 19 +++++++++++-------- 1 file changed, 11 insertions(+), 8 deletions(-)
diff --git a/init/main.c b/init/main.c
index 4425d17..7e9c0ca 100644
--- a/init/main.c
+++ b/init/main.c@@ -1088,14 +1088,6 @@ asmlinkage __visible void __init __no_sanitize_address start_kernel(void) */ locking_selftest(); - /* - * This needs to be called before any devices perform DMA - * operations that might use the SWIOTLB bounce buffers. It will - * mark the bounce buffers as decrypted so that their usage will - * not cause "plain-text" data to be decrypted when accessed. - */ - mem_encrypt_init(); - #ifdef CONFIG_BLK_DEV_INITRD if (initrd_start && !initrd_below_start_ok && page_to_pfn(virt_to_page((void *)initrd_start)) < min_low_pfn) {
@@ -1112,6 +1104,17 @@ asmlinkage __visible void __init __no_sanitize_address start_kernel(void) late_time_init(); sched_clock_init(); calibrate_delay(); + + /* + * This needs to be called before any devices perform DMA + * operations that might use the SWIOTLB bounce buffers. It will + * mark the bounce buffers as decrypted so that their usage will + * not cause "plain-text" data to be decrypted when accessed. It + * must be called after late_time_init() so that Hyper-V x86/x64 + * hypercalls work when the SWIOTLB bounce buffers are decrypted. + */ + mem_encrypt_init(); + pid_idr_init(); anon_vma_init(); #ifdef CONFIG_X86
--
1.8.3.1