RE: [BUG] Kernel panic when using Hibernation on kernel 6.1.25

[Jia-hao Bai (白家豪)]

Hi Pavel,

Hardware: Arm Cortex A55, 1GB RAM, eMMC 8G.

Error log：
[ 1362.985700] sh:  notify_die from die+0x144/0x5f0
[ 1362.985700] sh:  die from die_kernel_fault+0x138/0x148
[ 1362.985700] sh:  die_kernel_fault from __do_kernel_fault.part.0+0x5c/0xac
[ 1362.985700] sh:  __do_kernel_fault.part.0 from do_translation_fault+0xbc/0xe0
[ 1362.985700] sh:  do_translation_fault from do_DataAbort+0x44/0x1d0
[ 1362.985700] sh:  do_DataAbort from __dabt_svc+0x4c/0x80
[ 1362.985700] sh: Exception stack(0xc1e8df38 to 0xc1e8df80)
[ 1362.985700] sh: df20:                                                       c3000000 00000000
[ 1362.985700] sh: df40: c3001000 ea157ffc ea158000 c17639a8 c17bd548 edceb060 c184b540 c17bd5a0
[ 1362.985700] sh: df60: 00007fd7 ed76c000 00000000 c1e8df88 c0ebe4dc c0ebe4e4 800001d3 ffffffff
[ 1362.985700] sh:  __dabt_svc from safe_copy_page+0x20/0x4c
[ 1362.985700] sh:  safe_copy_page from swsusp_save+0x580/0x5ac
[ 1362.985700] sh:  swsusp_save from arch_save_image+0x8/0x74
[ 1362.985700] sh:  arch_save_image from cpu_suspend_abort+0x0/0x18

We compared between K5.4 and K6.1.25 and found that Hibernation does not save the reserve area on K5.4 because it is blocked by pfn_valid.

Therefore, we have added the following workaround to skip some reserved memory sections.

The skip region is obtained from "cat /proc/iomem".
40000000-42fbffff : System RAM
  40008000-410fffff : Kernel code
  41200000-4144a25f : Kernel data
43100000-4402ffff : System RAM
45140000-593fffff : System RAM
59401000-5940ffff : System RAM
5941f000-594effff : System RAM
59501180-595fffff : System RAM
59640000-7fffffff : System RAM

static unsigned int pfn_is_reserved(unsigned long pfn){
	phys_addr_t phys = __pfn_to_phy
	if(phys >= 0x42fc0000 && phys< 0x43100000){
		return true;
	}
	if(phys >= 0x44030000 && phys< 0x45140000){
		return true;
	}
	if(phys >= 0x59400000 && phys< 0x59401000){
		return true;
	}
	if(phys >= 0x59410000 && phys< 0x5941f000){
		return true;
	}
	if(phys >= 0x594f0000 && phys< 0x59501180){
		return true;
	}
        if(phys >= 0x59600000 && phys< 0x59640000){
                return true;
        }
	return false;

}

static struct page *saveable_page(struct zone *zone, unsigned long pfn)
{
	struct page *page;

	if (!pfn_valid(pfn)){
		return NULL;
	}
	
	if(pfn_is_reserved(pfn))
		 return NULL;
........


Do you know of any patches that can fix this problem?

thanks

-----Original Message-----
From: Pavel Machek <pavel@xxxxxx> 
Sent: Thursday, June 13, 2024 6:52 PM
To: Jia-hao Bai (白家豪) <Jia-hao.Bai@xxxxxxxxxxxx>
Cc: linux-kernel@xxxxxxxxxxxxxxx; rafael@xxxxxxxxxx; Iverlin Wang (王苳霖) <Iverlin.Wang@xxxxxxxxxxxx>; Boy Wu (吳勃誼) <Boy.Wu@xxxxxxxxxxxx>; Seiya Wang (王迺君) <seiya.wang@xxxxxxxxxxxx>; Dengjun Su (苏邓军) <Dengjun.Su@xxxxxxxxxxxx>; Win Yeh (葉昌倫) <Win.Yeh@xxxxxxxxxxxx>; Sowell Peng (彭首偉) <Sowell.Peng@xxxxxxxxxxxx>; Richard-CC Yang (楊職銓) <Richard-CC.Yang@xxxxxxxxxxxx>
Subject: Re: [BUG] Kernel panic when using Hibernation on kernel 6.1.25

Hi!

> I encountered a kernel panic when using the Hibernation on kernel version 6.1.25. Below are the details of the issue:
> 
> **Description:**
> When I enable CONFIG_HIBERNATION and assign a specific partition for hibernation resuming and perform a specific operation, the system crashes with a kernel panic.
> 
> CONFIG_HIBERNATION=y
> CONFIG_PM_STD_PARTITION="/dev/mmcblk0p16"
> 
> **Steps to Reproduce:**
> 1.	Set printk to level 8: ` echo 8 > /proc/sys/kernel/printk`
> 2.	Set up the swap partition: ` mkswap /dev/mmcblk0p16`
> 3.	Enable the swap partition: ` swapon -p -3 /dev/mmcblk0p16`
> 4.	Configure hibernation resuming settings: ` echo "/dev/mmcblk0p16" > /sys/power/resume`
> 5.	Configure hibernation mode:` echo reboot > /sys/power/disk`
> 6.	Perform the operation: ` echo disk > /sys/power/state`
> 7.	Observe the kernel panic
> 
> 
> **Expected Behavior:**
> The operation should complete successfully without causing a kernel panic.
> 
> **Actual Behavior:**
> The system crashes with a kernel panic.
> 
> **Environment:**
> - Kernel version: 6.1.25
> - Distribution: Yocto 4.0 32bit/Kernel 6.1.25 32bit
> - Hardware: Arm Cortex A55, 1GB RAM

We'd need to know way more about the hardware. Also testing with latest mainline would be useful.

Best regards,
							Pavel
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