Unverified Commit da06cc5b authored by Palmer Dabbelt's avatar Palmer Dabbelt
Browse files

RISC-V: fixups to work with crash tool 

A handful of fixes to our kexec/crash kernel support that allow crash
tool to function.

Link: https://lore.kernel.org/r/mhng-f5fdaa37-e99a-4214-a297-ec81f0fed0c1@palmer-mbp2014

* commit 'f9293ad4':
  RISC-V: Add modules to virtual kernel memory layout dump
  RISC-V: Fixup schedule out issue in machine_crash_shutdown()
  RISC-V: Fixup get incorrect user mode PC for kernel mode regs
  RISC-V: kexec: Fixup use of smp_processor_id() in preemptible context
parents 76ad33e1 f9293ad4

arch/riscv/kernel/crash_save_regs.S

+1 −1
Original line number Original line Diff line number Diff line
@@ -44,7 +44,7 @@ SYM_CODE_START(riscv_crash_save_regs) 
	REG_S t6,  PT_T6(a0)	/* x31 */

	REG_S t6,  PT_T6(a0)	/* x31 */





	csrr t1, CSR_STATUS

	csrr t1, CSR_STATUS

	csrr t2, CSR_EPC

	auipc t2, 0x0

	csrr t3, CSR_TVAL

	csrr t3, CSR_TVAL

	csrr t4, CSR_CAUSE

	csrr t4, CSR_CAUSE

arch/riscv/kernel/machine_kexec.c

+23 −5
Original line number Original line Diff line number Diff line
@@ -138,19 +138,37 @@ void machine_shutdown(void) 
#endif

#endif

}

}





/* Override the weak function in kernel/panic.c */

void crash_smp_send_stop(void)

{

	static int cpus_stopped;



	/*

	 * This function can be called twice in panic path, but obviously

	 * we execute this only once.

	 */

	if (cpus_stopped)

		return;



	smp_send_stop();

	cpus_stopped = 1;

}



/*

/*

 * machine_crash_shutdown - Prepare to kexec after a kernel crash

 * machine_crash_shutdown - Prepare to kexec after a kernel crash

 *

 *

 * This function is called by crash_kexec just before machine_kexec

 * This function is called by crash_kexec just before machine_kexec

 * below and its goal is similar to machine_shutdown, but in case of

 * and its goal is to shutdown non-crashing cpus and save registers.

 * a kernel crash. Since we don't handle such cases yet, this function

 * is empty.

 */

 */

void

void

machine_crash_shutdown(struct pt_regs *regs)

machine_crash_shutdown(struct pt_regs *regs)

{

{

	local_irq_disable();



	/* shutdown non-crashing cpus */

	crash_smp_send_stop();



	crash_save_cpu(regs, smp_processor_id());

	crash_save_cpu(regs, smp_processor_id());

	machine_shutdown();

	pr_info("Starting crashdump kernel...\n");

	pr_info("Starting crashdump kernel...\n");

}

}
@@ -171,7 +189,7 @@ machine_kexec(struct kimage *image) 
	struct kimage_arch *internal = &image->arch;

	struct kimage_arch *internal = &image->arch;

	unsigned long jump_addr = (unsigned long) image->start;

	unsigned long jump_addr = (unsigned long) image->start;

	unsigned long first_ind_entry = (unsigned long) &image->head;

	unsigned long first_ind_entry = (unsigned long) &image->head;

	unsigned long this_cpu_id = smp_processor_id();

	unsigned long this_cpu_id = __smp_processor_id();

	unsigned long this_hart_id = cpuid_to_hartid_map(this_cpu_id);

	unsigned long this_hart_id = cpuid_to_hartid_map(this_cpu_id);

	unsigned long fdt_addr = internal->fdt_addr;

	unsigned long fdt_addr = internal->fdt_addr;

	void *control_code_buffer = page_address(image->control_code_page);

	void *control_code_buffer = page_address(image->control_code_page);

arch/riscv/mm/init.c

+4 −0
Original line number Original line Diff line number Diff line
@@ -135,6 +135,10 @@ static void __init print_vm_layout(void) 
		(unsigned long)VMEMMAP_END);

		(unsigned long)VMEMMAP_END);

	print_ml("vmalloc", (unsigned long)VMALLOC_START,

	print_ml("vmalloc", (unsigned long)VMALLOC_START,

		(unsigned long)VMALLOC_END);

		(unsigned long)VMALLOC_END);

#ifdef CONFIG_64BIT

	print_ml("modules", (unsigned long)MODULES_VADDR,

		(unsigned long)MODULES_END);

#endif

	print_ml("lowmem", (unsigned long)PAGE_OFFSET,

	print_ml("lowmem", (unsigned long)PAGE_OFFSET,

		(unsigned long)high_memory);

		(unsigned long)high_memory);

	if (IS_ENABLED(CONFIG_64BIT)) {

	if (IS_ENABLED(CONFIG_64BIT)) {