On 07/13/24 at 09:48am, Jinjie Ruan wrote: > 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. I am not sure if this is a good idea. Shouldn't we handle this in arch_reserve_crashkernel() to check the system RAM size? With this patch, if you specify crashkernel=4352M (namely 4G+256M) in kernel cmdline, then you will reserve 256M crashkernel in system, don't you think that is confusing? By the way, I am considering changing code to apply generic crashkernel reservation to 32bit system. Maybe below draft code can prevent crashkernel=,high from being parsed successfully on 32bit system. What do you think? diff --git a/arch/arm64/include/asm/crash_reserve.h b/arch/arm64/include/asm/crash_reserve.h index 4afe027a4e7b..bf362c1a612f 100644 --- a/arch/arm64/include/asm/crash_reserve.h +++ b/arch/arm64/include/asm/crash_reserve.h @@ -7,4 +7,6 @@ #define CRASH_ADDR_LOW_MAX arm64_dma_phys_limit #define CRASH_ADDR_HIGH_MAX (PHYS_MASK + 1) + +#define HAVE_ARCH_CRASHKERNEL_RESERVATION_HIGH #endif diff --git a/arch/riscv/include/asm/crash_reserve.h b/arch/riscv/include/asm/crash_reserve.h index 013962e63587..8d7a8fc1d459 100644 --- a/arch/riscv/include/asm/crash_reserve.h +++ b/arch/riscv/include/asm/crash_reserve.h @@ -7,5 +7,7 @@ #define CRASH_ADDR_LOW_MAX dma32_phys_limit #define CRASH_ADDR_HIGH_MAX memblock_end_of_DRAM() +#define HAVE_ARCH_CRASHKERNEL_RESERVATION_HIGH + extern phys_addr_t memblock_end_of_DRAM(void); #endif diff --git a/arch/x86/include/asm/crash_reserve.h b/arch/x86/include/asm/crash_reserve.h index 7835b2cdff04..24c2327f9a16 100644 --- a/arch/x86/include/asm/crash_reserve.h +++ b/arch/x86/include/asm/crash_reserve.h @@ -26,6 +26,7 @@ extern unsigned long swiotlb_size_or_default(void); #else # define CRASH_ADDR_LOW_MAX SZ_4G # define CRASH_ADDR_HIGH_MAX SZ_64T +#define HAVE_ARCH_CRASHKERNEL_RESERVATION_HIGH #endif # define DEFAULT_CRASH_KERNEL_LOW_SIZE crash_low_size_default() diff --git a/kernel/crash_reserve.c b/kernel/crash_reserve.c index 5b2722a93a48..c5213f123e19 100644 --- a/kernel/crash_reserve.c +++ b/kernel/crash_reserve.c @@ -306,7 +306,7 @@ int __init parse_crashkernel(char *cmdline, /* crashkernel=X[@offset] */ ret = __parse_crashkernel(cmdline, system_ram, crash_size, crash_base, NULL); -#ifdef CONFIG_ARCH_HAS_GENERIC_CRASHKERNEL_RESERVATION +#ifdef HAVE_ARCH_CRASHKERNEL_RESERVATION_HIGH /* * If non-NULL 'high' passed in and no normal crashkernel * setting detected, try parsing crashkernel=,high|low. _______________________________________________ kexec mailing list kexec@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/kexec
