commit 4db444b9a78abf9f6dc981f0e79db749765dc6e8
author José Martínez <xose@google.com> Tue Jun 13 11:01:34 2023 -0400
committer Kevin O'Connor <kevin@koconnor.net> Tue Jun 13 11:01:34 2023 -0400
tree 12345770c63bb1b86fe295a315fe3f04e5a86a5a
parent be7e899350caa7b74d8271a34264c3b4aef25ab0

Fix high memory zone initialization in CSM mode

malloc_high() cannot allocate any memory in CSM mode due to an empty
ZoneHigh. SeaBIOS cannot find any disk to boot from because device
initialization fails.

The bug was introduced in 1.16.1 (commit dc88f9b) when the meaning of
BUILD_MAX_HIGHTABLE changed but CSM code was not updated. This patch
reverts to the previous behavior by using BUILD_MIN_HIGHTABLE in CSM
methods.

Signed-off-by: José Martínez <xose@google.com>

src/fw/csm.c

diff --git a/src/fw/csm.c b/src/fw/csm.c
index bc14a92..579debd 100644
--- a/src/fw/csm.c
+++ b/src/fw/csm.c
@@ -150,9 +150,9 @@
     for (i=0; i < csm_compat_table.E820Length / sizeof(struct e820entry); i++)
         e820_add(p[i].start, p[i].size, p[i].type);
 
-    if (csm_init_table->HiPmmMemorySizeInBytes > BUILD_MAX_HIGHTABLE) {
+    if (csm_init_table->HiPmmMemorySizeInBytes > BUILD_MIN_HIGHTABLE) {
         u32 hi_pmm_end = csm_init_table->HiPmmMemory + csm_init_table->HiPmmMemorySizeInBytes;
-        e820_add(hi_pmm_end - BUILD_MAX_HIGHTABLE, BUILD_MAX_HIGHTABLE, E820_RESERVED);
+        e820_add(hi_pmm_end - BUILD_MIN_HIGHTABLE, BUILD_MIN_HIGHTABLE, E820_RESERVED);
     }
 
     // For PCIBIOS 1ab10e

src/malloc.c

diff --git a/src/malloc.c b/src/malloc.c
index da84098..30b2c92 100644
--- a/src/malloc.c
+++ b/src/malloc.c
@@ -460,10 +460,10 @@
 {
     ASSERT32FLAT();
 
-    if (hi_pmm_size > BUILD_MAX_HIGHTABLE) {
+    if (hi_pmm_size > BUILD_MIN_HIGHTABLE) {
         u32 hi_pmm_end = hi_pmm + hi_pmm_size;
-        alloc_add(&ZoneTmpHigh, hi_pmm, hi_pmm_end - BUILD_MAX_HIGHTABLE);
-        alloc_add(&ZoneHigh, hi_pmm_end - BUILD_MAX_HIGHTABLE, hi_pmm_end);
+        alloc_add(&ZoneTmpHigh, hi_pmm, hi_pmm_end - BUILD_MIN_HIGHTABLE);
+        alloc_add(&ZoneHigh, hi_pmm_end - BUILD_MIN_HIGHTABLE, hi_pmm_end);
     } else {
         alloc_add(&ZoneTmpHigh, hi_pmm, hi_pmm + hi_pmm_size);
     }