On 04/14/23 at 03:34pm, Will Deacon wrote: > Hi, > > On Fri, Apr 07, 2023 at 10:24:19AM +0800, Baoquan He wrote: > > On arm64, reservation for 'crashkernel=xM,high' is taken by searching for > > suitable memory region top down. If the 'xM' of crashkernel high memory > > is reserved from high memory successfully, it will try to reserve > > crashkernel low memory later accoringly. Otherwise, it will try to search > > low memory area for the 'xM' suitable region. Please see the details in > > Documentation/admin-guide/kernel-parameters.txt. > > [...] > > > arch/arm64/mm/init.c | 44 ++++++++++++++++++++++++++++++++++---------- > > 1 file changed, 34 insertions(+), 10 deletions(-) > > I tried to apply this, but smatch is unhappy with the result: > > | arch/arm64/mm/init.c:153 reserve_crashkernel() error: uninitialized symbol 'search_base'. > > I _think_ this is a false positive, but I must say that the control flow > in reserve_crashkernel() is extremely hard to follow so I couldn't be > sure. If the static checker is struggling, then so will humans! > > Ideally, this would all be restructured to make it easier to follow, > but in the short term we need something to squash the warning. Sorry for that, I didn't run static checker. We should do initialization as below to fix the warning. Below code can be added into this v5 patch, or I can post v6 with Catalin's Reviewed-by tag. Yes, about restructuring, I can think about it later. The added corner cases handling specific for arm64 makes the flow a little harder to flow. I will consider if adding document in arm64 is better. >From 3575571ab9614c31f30933148a8693924a30321c Mon Sep 17 00:00:00 2001 From: Baoquan He <bhe@xxxxxxxxxx> Date: Sat, 15 Apr 2023 08:35:08 +0800 Subject: [PATCH] arm64: kdump: fix warning reported by static checker Content-type: text/plain Signed-off-by: Baoquan He <bhe@xxxxxxxxxx> --- arch/arm64/mm/init.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c index 13750b0548da..bfc117cefcd5 100644 --- a/arch/arm64/mm/init.c +++ b/arch/arm64/mm/init.c @@ -128,9 +128,9 @@ static int __init reserve_crashkernel_low(unsigned long long low_size) */ static void __init reserve_crashkernel(void) { - unsigned long long crash_base, crash_size, search_base; + unsigned long long crash_low_size = 0, search_base = 0; unsigned long long crash_max = CRASH_ADDR_LOW_MAX; - unsigned long long crash_low_size = 0; + unsigned long long crash_base, crash_size; char *cmdline = boot_command_line; bool fixed_base = false; bool high = false; -- 2.34.1 _______________________________________________ kexec mailing list kexec@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/kexec