[PATCH v2] crash: Fix x86_32 and arm32 memory reserve bug

From: Jinjie Ruan
Date: Fri Jul 12 2024 - 21:44:01 EST


On x86_32 Qemu machine with 1GB memory, the cmdline "crashkernel=4G" is ok
as below:
crashkernel reserved: 0x0000000020000000 - 0x0000000120000000 (4096 MB)

And on Qemu vexpress-a9 with 1GB memory, the crash kernel "crashkernel=4G"
is also ok as below:
Reserving 4096MB of memory at 2432MB for crashkernel (System RAM: 1024MB)

The cause is that the crash_size is parsed and printed with "unsigned long
long" data type which is 8 bytes but allocated used with "phys_addr_t"
which is 4 bytes in memblock_phys_alloc_range().

Fix it by limiting the "crash_size" to phys_addr_t and bypass the invalid
input size.

After this patch, it fail as expected and no above confusing reserve
success info.

Fixes: 9d17f3372306 ("ARM: 9190/1: kdump: add invalid input check for 'crashkernel=0'")
Signed-off-by: Jinjie Ruan <ruanjinjie@xxxxxxxxxx>
---
v2:
- Also fix for x86_32.
- Update the fix method.
- Peel off the other two patches.
- Update the commit message.
---
kernel/crash_reserve.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/kernel/crash_reserve.c b/kernel/crash_reserve.c
index 5073ae205f79..5c2148d89da6 100644
--- a/kernel/crash_reserve.c
+++ b/kernel/crash_reserve.c
@@ -314,7 +314,7 @@ int __init parse_crashkernel(char *cmdline,
if (high && ret == -ENOENT) {
ret = __parse_crashkernel(cmdline, 0, crash_size,
crash_base, suffix_tbl[SUFFIX_HIGH]);
- if (ret || !*crash_size)
+ if (ret || !(phys_addr_t)*crash_size)
return -EINVAL;

/*
@@ -333,7 +333,7 @@ int __init parse_crashkernel(char *cmdline,
*high = true;
}
#endif
- if (!*crash_size)
+ if (!(phys_addr_t)*crash_size)
ret = -EINVAL;

return ret;
--
2.34.1