git: 46bb2dca534a - main - kasan: Increase the size of the bootstrap PTP reservation

The branch main has been updated by markj:

URL: https://cgit.FreeBSD.org/src/commit/?id=46bb2dca534ae1dfe95ea11c915b441e4867a310

commit 46bb2dca534ae1dfe95ea11c915b441e4867a310
Author:     Mark Johnston <markj@FreeBSD.org>
AuthorDate: 2024-06-16 17:33:13 +0000
Commit:     Mark Johnston <markj@FreeBSD.org>
CommitDate: 2024-06-16 17:33:13 +0000

    kasan: Increase the size of the bootstrap PTP reservation
    
    We were undercounting in the case where the boot stack crosses a 2MB
    boundary, resulting in a panic during locore execution.
    
    MFC after:      1 week
    Fixes:  756bc3adc578 ("kasan: Create a shadow for the bootstack prior to hammer_time()")
---
 sys/amd64/amd64/pmap.c | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/sys/amd64/amd64/pmap.c b/sys/amd64/amd64/pmap.c
index dee208fc9145..57943e815b5b 100644
--- a/sys/amd64/amd64/pmap.c
+++ b/sys/amd64/amd64/pmap.c
@@ -11671,15 +11671,16 @@ pmap_pkru_clear(pmap_t pmap, vm_offset_t sva, vm_offset_t eva)
  * Reserve enough memory to:
  * 1) allocate PDP pages for the shadow map(s),
  * 2) shadow the boot stack of KSTACK_PAGES pages,
- * so we need one PD page, one or two PT pages, and KSTACK_PAGES shadow pages
- * per shadow map.
+ * 3) assuming that the kernel stack does not cross a 1GB boundary,
+ * so we need one or two PD pages, one or two PT pages, and KSTACK_PAGES shadow
+ * pages per shadow map.
  */
 #ifdef KASAN
 #define	SAN_EARLY_PAGES	\
-	(NKASANPML4E + 1 + 2 + howmany(KSTACK_PAGES, KASAN_SHADOW_SCALE))
+	(NKASANPML4E + 2 + 2 + howmany(KSTACK_PAGES, KASAN_SHADOW_SCALE))
 #else
 #define	SAN_EARLY_PAGES	\
-	(NKMSANSHADPML4E + NKMSANORIGPML4E + 2 * (1 + 2 + KSTACK_PAGES))
+	(NKMSANSHADPML4E + NKMSANORIGPML4E + 2 * (2 + 2 + KSTACK_PAGES))
 #endif
 
 static uint64_t __nosanitizeaddress __nosanitizememory