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Date:      Fri, 29 May 2026 22:08:23 +0000
From:      Mark Johnston <markj@FreeBSD.org>
To:        src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-branches@FreeBSD.org
Cc:        Zishun Yi <zis@FreeBSD.org>
Subject:   git: 048458a434a1 - stable/15 - amd64/vmparam: Fix KASAN shadow map size in comment
Message-ID:  <6a1a0e57.3d028.77a06f05@gitrepo.freebsd.org>
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The branch stable/15 has been updated by markj:

URL: https://cgit.FreeBSD.org/src/commit/?id=048458a434a13e587d873039f931489f9b9e60aa

commit 048458a434a13e587d873039f931489f9b9e60aa
Author:     Zishun Yi <zis@FreeBSD.org>
AuthorDate: 2026-05-20 14:34:08 +0000
Commit:     Mark Johnston <markj@FreeBSD.org>
CommitDate: 2026-05-29 19:46:48 +0000

    amd64/vmparam: Fix KASAN shadow map size in comment
    
    The address range 0xfffff78000000000 - 0xfffff7bfffffffff spans exactly 256GB
    (0x4000000000 bytes), not 512GB.
    
    For a 2TB kernel map, based on the KASAN 1:8 shadow map ratio, the required
    shadow map size is indeed 256GB. The current comment incorrectly states 512GB,
    which can be misleading and cause confusion.
    
    Reviewed by:    markj
    MFC after:      1 week
    Differential Revision:  https://reviews.freebsd.org/D57129
    
    (cherry picked from commit b36fd09a834be586fbc1630294e17554e1f76175)
---
 sys/amd64/include/vmparam.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/sys/amd64/include/vmparam.h b/sys/amd64/include/vmparam.h
index d2ac3c6648b2..763b89da9e12 100644
--- a/sys/amd64/include/vmparam.h
+++ b/sys/amd64/include/vmparam.h
@@ -171,7 +171,7 @@
  * 0xffff808000000000 - 0xffff847fffffffff   large map (can be tuned up)
  * 0xffff848000000000 - 0xfffff77fffffffff   unused (large map extends there)
  * 0xfffff60000000000 - 0xfffff7ffffffffff   2TB KMSAN origin map, optional
- * 0xfffff78000000000 - 0xfffff7bfffffffff   512GB KASAN shadow map, optional
+ * 0xfffff78000000000 - 0xfffff7bfffffffff   256GB KASAN shadow map, optional
  * 0xfffff80000000000 - 0xfffffbffffffffff   4TB direct map
  * 0xfffffc0000000000 - 0xfffffdffffffffff   2TB KMSAN shadow map, optional
  * 0xfffffe0000000000 - 0xffffffffffffffff   2TB kernel map
@@ -185,7 +185,7 @@
  * 0xff41000000000000 - 0xffff7fffffffffff   unused
  * 0xffff800000000000 - 0xfffff5ffffffffff   unused (start of kernel pml4 entry)
  * 0xfffff60000000000 - 0xfffff7ffffffffff   2TB KMSAN origin map, optional
- * 0xfffff78000000000 - 0xfffff7bfffffffff   512GB KASAN shadow map, optional
+ * 0xfffff78000000000 - 0xfffff7bfffffffff   256GB KASAN shadow map, optional
  * 0xfffff80000000000 - 0xfffffbffffffffff   4TB unused
  * 0xfffffc0000000000 - 0xfffffdffffffffff   2TB KMSAN shadow map, optional
  * 0xfffffe0000000000 - 0xffffffffffffffff   2TB kernel map
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