The quilt patch titled
Subject: kexec: improve the readability of crash_shrink_memory()
has been removed from the -mm tree. Its filename was
kexec-improve-the-readability-of-crash_shrink_memory.patch
This patch was dropped because it was merged into the mm-nonmm-stable branch
of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
------------------------------------------------------
From: Zhen Lei <thunder.leizhen@xxxxxxxxxx>
Subject: kexec: improve the readability of crash_shrink_memory()
Date: Sat, 27 May 2023 20:34:37 +0800
The major adjustments are:
1. end = start + new_size.
The 'end' here is not an accurate representation, because it is not the
new end of crashk_res, but the start of ram_res, difference 1. So
eliminate it and replace it with ram_res->start.
2. Use 'ram_res->start' and 'ram_res->end' as arguments to
crash_free_reserved_phys_range() to indicate that the memory covered by
'ram_res' is released from the crashk. And keep it close to
insert_resource().
3. Replace 'if (start == end)' with 'if (!new_size)', clear indication that
all crashk memory will be shrunken.
No functional change.
Link: https://lkml.kernel.org/r/20230527123439.772-5-thunder.leizhen@xxxxxxxxxx
Signed-off-by: Zhen Lei <thunder.leizhen@xxxxxxxxxx>
Acked-by: Baoquan He <bhe@xxxxxxxxxx>
Cc: Cong Wang <amwang@xxxxxxxxxx>
Cc: Eric W. Biederman <ebiederm@xxxxxxxxxxxx>
Cc: Michael Holzheu <holzheu@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
kernel/kexec_core.c | 15 +++++----------
1 file changed, 5 insertions(+), 10 deletions(-)
--- a/kernel/kexec_core.c~kexec-improve-the-readability-of-crash_shrink_memory
+++ a/kernel/kexec_core.c
@@ -1108,7 +1108,6 @@ ssize_t crash_get_memory_size(void)
int crash_shrink_memory(unsigned long new_size)
{
int ret = 0;
- unsigned long start, end;
unsigned long old_size;
struct resource *ram_res;
@@ -1119,9 +1118,7 @@ int crash_shrink_memory(unsigned long ne
ret = -ENOENT;
goto unlock;
}
- start = crashk_res.start;
- end = crashk_res.end;
- old_size = (end == 0) ? 0 : end - start + 1;
+ old_size = !crashk_res.end ? 0 : resource_size(&crashk_res);
new_size = roundup(new_size, KEXEC_CRASH_MEM_ALIGN);
if (new_size >= old_size) {
ret = (new_size == old_size) ? 0 : -EINVAL;
@@ -1134,22 +1131,20 @@ int crash_shrink_memory(unsigned long ne
goto unlock;
}
- end = start + new_size;
- crash_free_reserved_phys_range(end, crashk_res.end);
-
- ram_res->start = end;
+ ram_res->start = crashk_res.start + new_size;
ram_res->end = crashk_res.end;
ram_res->flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM;
ram_res->name = "System RAM";
- if (start == end) {
+ if (!new_size) {
release_resource(&crashk_res);
crashk_res.start = 0;
crashk_res.end = 0;
} else {
- crashk_res.end = end - 1;
+ crashk_res.end = ram_res->start - 1;
}
+ crash_free_reserved_phys_range(ram_res->start, ram_res->end);
insert_resource(&iomem_resource, ram_res);
unlock:
_
Patches currently in -mm which might be from thunder.leizhen@xxxxxxxxxx are
kexec-add-helper-__crash_shrink_memory.patch
kexec-enable-kexec_crash_size-to-support-two-crash-kernel-regions.patch
