[RFC V1 5/5] x86: CVMs: Ensure that memory conversions happen at 2M alignment

From: Vishal Annapurve
Date: Fri Jan 12 2024 - 00:54:17 EST


Return error on conversion of memory ranges not aligned to 2M size.

Signed-off-by: Vishal Annapurve <vannapurve@xxxxxxxxxx>
---
arch/x86/mm/pat/set_memory.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/arch/x86/mm/pat/set_memory.c b/arch/x86/mm/pat/set_memory.c
index bda9f129835e..6f7b06a502f4 100644
--- a/arch/x86/mm/pat/set_memory.c
+++ b/arch/x86/mm/pat/set_memory.c
@@ -2133,8 +2133,10 @@ static int __set_memory_enc_pgtable(unsigned long addr, int numpages, bool enc)
int ret;

/* Should not be working on unaligned addresses */
- if (WARN_ONCE(addr & ~PAGE_MASK, "misaligned address: %#lx\n", addr))
- addr &= PAGE_MASK;
+ if (WARN_ONCE(addr & ~HPAGE_MASK, "misaligned address: %#lx\n", addr)
+ || WARN_ONCE((numpages << PAGE_SHIFT) & ~HPAGE_MASK,
+ "misaligned numpages: %#lx\n", numpages))
+ return -EINVAL;

memset(&cpa, 0, sizeof(cpa));
cpa.vaddr = &addr;
--
2.43.0.275.g3460e3d667-goog