+++ /dev/null
-This patch updates kernel part of kexec for MIPS platform to support
-kdump, 64-bit, SMP and simplify code adaptation to new boards. It does
-the following:
-
-- hooks for machine-specific actions are introduced
-(_machine_kexec_prepare,
- _machine_kexec_shutdown, _machine_crash_shutdown);
-- kexec reboot on SMP machine is implemented;
-- add boot parameters passing to new kernel (array kexec_args[] is
-copied to
- registers a0-a3 on reboot );
-- crash dump functionality is added (boot kernel with non-default physical
- start, parse "crashkernel=..." command line parameter, copy_oldmem_page()
- is implemeted to read memory dump after reboot-on-crashi,
-crash_setup_regs()
- is updated to correctly store registers on crash);
-
-kexec/kdump funtionality was tested on several Cavium Octeon boards
-(mips64 SMP). The way we do it was the following:
-- _machine_kexec_prepare was find kexec segment with command line and
-save it's pointed into internal bootloader structure.
-- _machine_kexec_shutdown was used to stop boards IO and make all non-boot
-CPUs spin in function relocated_kexec_smp_wait()
-- _machine_crash_shutdown just calls default_machine_crash_shutdown()
-We tested 1) 'common' kexec reboot (by 'kexec -e'), 2) kexec-on-panic
-('kexec -p ...') and 3) access to/proc/vmcore (with gdb).
-
-Signed-off-by: Maxim Syrchin <[11]msyrchin at ru.mvista.com>
----
-arch/mips/Kconfig | 23 +++++++++
-arch/mips/Makefile | 4 ++
-arch/mips/kernel/Makefile | 3 +-
-arch/mips/kernel/crash.c | 91 ++++++++++++++++++++++++++++++++++
-arch/mips/kernel/crash_dump.c | 96 ++++++++++++++++++++++++++++++++++++
-arch/mips/kernel/machine_kexec.c | 52 ++++++++++++++++++-
-arch/mips/kernel/relocate_kernel.S | 93 ++++++++++++++++++++++++++++++++++-
-arch/mips/kernel/setup.c | 10 +++-
-arch/mips/include/asm/kexec.h | 21 ++++++++-
-9 files changed, 386 insertions(+), 7 deletions(-)
-create mode 100644 arch/mips/kernel/crash.c
-create mode 100644 arch/mips/kernel/crash_dump.c
-
----
- arch/mips/Kconfig | 23 23 + 0 - 0 !
- arch/mips/Makefile | 4 4 + 0 - 0 !
- arch/mips/kernel/Makefile | 3 2 + 1 - 0 !
- arch/mips/kernel/crash.c | 90 90 + 0 - 0 !
- arch/mips/kernel/crash_dump.c | 96 96 + 0 - 0 !
- arch/mips/kernel/machine_kexec.c | 66 60 + 6 - 0 !
- arch/mips/kernel/relocate_kernel.S | 96 95 + 1 - 0 !
- arch/mips/kernel/setup.c | 10 9 + 1 - 0 !
- arch/mips/include/asm/kexec.h | 21 20 + 1 - 0 !
- 9 files changed, 399 insertions(+), 10 deletions(-)
-
---- a/arch/mips/Kconfig
-+++ b/arch/mips/Kconfig
-@@ -1966,6 +1966,29 @@ config KEXEC
- support. As of this writing the exact hardware interface is
- strongly in flux, so no good recommendation can be made.
-
-+config CRASH_DUMP
-+ bool "kernel crash dumps (EXPERIMENTAL)"
-+ depends on EXPERIMENTAL
-+ help
-+ Generate crash dump after being started by kexec.
-+ This should be normally only set in special crash dump kernels
-+ which are loaded in the main kernel with kexec-tools into
-+ a specially reserved region and then later executed after
-+ a crash by kdump/kexec. The crash dump kernel must be compiled
-+ to a memory address not used by the main kernel or BIOS using
-+ PHYSICAL_START.
-+
-+config PHYSICAL_START
-+ hex "Physical address where the kernel is loaded"
-+ default "0xffffffff84000000"
-+ depends on CRASH_DUMP
-+ help
-+ This gives the CKSEG0 or KSEG0 address where the kernel is loaded.
-+ If you plan to use kernel for capturing the crash dump change
-+ this value to start of the reserved region (the "X" value as
-+ specified in the "crashkernel=[12]YM at XM" command line boot parameter
-+ passed to the panic-ed kernel).
-+
- config SECCOMP
- bool "Enable seccomp to safely compute untrusted bytecode"
- depends on PROC_FS
---- a/arch/mips/Makefile
-+++ b/arch/mips/Makefile
-@@ -603,6 +603,10 @@ else
- load-$(CONFIG_CPU_CAVIUM_OCTEON) += 0xffffffff81100000
- endif
-
-+ifdef CONFIG_PHYSICAL_START
-+load-y = $(CONFIG_PHYSICAL_START)
-+endif
-+
- cflags-y += -I$(srctree)/arch/mips/include/asm/mach-generic
- drivers-$(CONFIG_PCI) += arch/mips/pci/
-
---- a/arch/mips/kernel/Makefile
-+++ b/arch/mips/kernel/Makefile
-@@ -83,7 +83,8 @@ obj-$(CONFIG_I8253) += i8253.o
-
- obj-$(CONFIG_GPIO_TXX9) += gpio_txx9.o
-
--obj-$(CONFIG_KEXEC) += machine_kexec.o relocate_kernel.o
-+obj-$(CONFIG_KEXEC) += machine_kexec.o relocate_kernel.o crash.o
-+obj-$(CONFIG_CRASH_DUMP) += crash_dump.o
- obj-$(CONFIG_EARLY_PRINTK) += early_printk.o
- obj-$(CONFIG_MIPS_MACHINE) += mips_machine.o
-
---- /dev/null
-+++ b/arch/mips/kernel/crash.c
-@@ -0,0 +1,90 @@
-+/*
-+ * Architecture specific (MIPS) functions for kexec based crash dumps.
-+ *
-+ * Copyright (C) 2005, IBM Corp.
-+ * Copyright (C) 2008, MontaVista Software Inc.
-+ *
-+ * This source code is licensed under the GNU General Public License,
-+ * Version 2. See the file COPYING for more details.
-+ *
-+ */
-+
-+#undef DEBUG
-+
-+#include <linux/kernel.h>
-+#include <linux/smp.h>
-+#include <linux/reboot.h>
-+#include <linux/kexec.h>
-+#include <linux/bootmem.h>
-+#include <linux/crash_dump.h>
-+#include <linux/delay.h>
-+#include <linux/init.h>
-+#include <linux/irq.h>
-+#include <linux/types.h>
-+#include <linux/sched.h>
-+
-+
-+
-+/* This keeps a track of which one is crashing cpu. */
-+int crashing_cpu = -1;
-+static cpumask_t cpus_in_crash = CPU_MASK_NONE;
-+
-+#ifdef CONFIG_SMP
-+
-+void crash_shutdown_secondary(void *ignore)
-+{
-+ struct pt_regs* regs;
-+ int cpu = smp_processor_id();
-+
-+ regs = task_pt_regs(current);
-+ if (!cpu_online(cpu))
-+ return;
-+
-+ local_irq_disable();
-+ if (!cpu_isset(cpu, cpus_in_crash))
-+ crash_save_cpu(regs, cpu);
-+ cpu_set(cpu, cpus_in_crash);
-+
-+ while(!atomic_read(&kexec_ready_to_reboot)) {
-+ cpu_relax();
-+ }
-+ relocated_kexec_smp_wait(NULL);
-+ /* NOTREACHED */
-+}
-+
-+static void crash_kexec_prepare_cpus(void)
-+{
-+ unsigned int msecs;
-+
-+ unsigned int ncpus = num_online_cpus() - 1;/* Excluding the panic cpu */
-+
-+ smp_call_function (crash_shutdown_secondary, NULL, 0);
-+ smp_wmb();
-+
-+ /*
-+ * FIXME: Until we will have the way to stop other CPUSs reliabally,
-+ * the crash CPU will send an IPI and wait for other CPUs to
-+ * respond.
-+ * Delay of at least 10 seconds.
-+ */
-+ printk(KERN_EMERG "Sending IPI to other cpus...\n");
-+ msecs = 10000;
-+ while ((cpus_weight(cpus_in_crash) < ncpus) && (--msecs > 0)) {
-+ cpu_relax();
-+ mdelay(1);
-+ }
-+
-+}
-+
-+#else
-+static void crash_kexec_prepare_cpus(void) {}
-+#endif
-+
-+void default_machine_crash_shutdown(struct pt_regs *regs)
-+{
-+ local_irq_disable();
-+ crashing_cpu = smp_processor_id();
-+ crash_save_cpu(regs, crashing_cpu);
-+ crash_kexec_prepare_cpus();
-+ cpu_set(crashing_cpu, cpus_in_crash);
-+}
---- /dev/null
-+++ b/arch/mips/kernel/crash_dump.c
-@@ -0,0 +1,96 @@
-+/*
-+ * Routines for doing kexec-based kdump.
-+ *
-+ * Copyright (C) 2005, IBM Corp.
-+ * Copyright (C) 2008, MontaVista Software Inc.
-+ *
-+ * This source code is licensed under the GNU General Public License,
-+ * Version 2. See the file COPYING for more details.
-+ */
-+
-+#include <linux/highmem.h>
-+#include <linux/bootmem.h>
-+#include <linux/crash_dump.h>
-+#include <asm/uaccess.h>
-+
-+#ifdef CONFIG_PROC_VMCORE
-+static int __init parse_elfcorehdr(char *p)
-+{
-+ if (p)
-+ elfcorehdr_addr = memparse(p, &p);
-+ return 1;
-+}
-+__setup("elfcorehdr=", parse_elfcorehdr);
-+#endif
-+
-+static int __init parse_savemaxmem(char *p)
-+{
-+ if (p)
-+ saved_max_pfn = (memparse(p, &p) >> PAGE_SHIFT) - 1;
-+
-+ return 1;
-+}
-+__setup("savemaxmem=", parse_savemaxmem);
-+
-+
-+static void *kdump_buf_page;
-+
-+/**
-+ * copy_oldmem_page - copy one page from "oldmem"
-+ * @pfn: page frame number to be copied
-+ * @buf: target memory address for the copy; this can be in kernel address
-+ * space or user address space (see @userbuf)
-+ * @csize: number of bytes to copy
-+ * @offset: offset in bytes into the page (based on pfn) to begin the copy
-+ * @userbuf: if set, @buf is in user address space, use copy_to_user(),
-+ * otherwise @buf is in kernel address space, use memcpy().
-+ *
-+ * Copy a page from "oldmem". For this page, there is no pte mapped
-+ * in the current kernel.
-+ *
-+ * Calling copy_to_user() in atomic context is not desirable. Hence first
-+ * copying the data to a pre-allocated kernel page and then copying to user
-+ * space in non-atomic context.
-+ */
-+ssize_t copy_oldmem_page(unsigned long pfn, char *buf,
-+ size_t csize, unsigned long offset, int userbuf)
-+{
-+ void *vaddr;
-+
-+ if (!csize)
-+ return 0;
-+
-+ vaddr = kmap_atomic_pfn(pfn, KM_PTE0);
-+
-+ if (!userbuf) {
-+ memcpy(buf, (vaddr + offset), csize);
-+ kunmap_atomic(vaddr, KM_PTE0);
-+ } else {
-+ if (!kdump_buf_page) {
-+ printk(KERN_WARNING "Kdump: Kdump buffer page not"
-+ " allocated\n");
-+ return -EFAULT;
-+ }
-+ copy_page(kdump_buf_page, vaddr);
-+ kunmap_atomic(vaddr, KM_PTE0);
-+ if (copy_to_user(buf, (kdump_buf_page + offset), csize))
-+ return -EFAULT;
-+ }
-+
-+ return csize;
-+}
-+
-+static int __init kdump_buf_page_init(void)
-+{
-+ int ret = 0;
-+
-+ kdump_buf_page = kmalloc(PAGE_SIZE, GFP_KERNEL);
-+ if (!kdump_buf_page) {
-+ printk(KERN_WARNING "Kdump: Failed to allocate kdump buffer"
-+ " page\n");
-+ ret = -ENOMEM;
-+ }
-+
-+ return ret;
-+}
-+arch_initcall(kdump_buf_page_init);
---- a/arch/mips/kernel/machine_kexec.c
-+++ b/arch/mips/kernel/machine_kexec.c
-@@ -19,9 +19,25 @@ extern const size_t relocate_new_kernel_
- extern unsigned long kexec_start_address;
- extern unsigned long kexec_indirection_page;
-
-+extern unsigned long fw_arg0, fw_arg1, fw_arg2, fw_arg3;
-+
-+int (*_machine_kexec_prepare)(struct kimage *) = NULL;
-+void (*_machine_kexec_shutdown)(void) = NULL;
-+void (*_machine_crash_shutdown)(struct pt_regs *regs) = NULL;
-+#ifdef CONFIG_SMP
-+void (*relocated_kexec_smp_wait) (void *);
-+atomic_t kexec_ready_to_reboot = ATOMIC_INIT(0);
-+#endif
-+
- int
- machine_kexec_prepare(struct kimage *kimage)
- {
-+ kexec_args[0] = fw_arg0;
-+ kexec_args[1] = fw_arg1;
-+ kexec_args[2] = fw_arg2;
-+ kexec_args[3] = fw_arg3;
-+ if (_machine_kexec_prepare)
-+ return _machine_kexec_prepare(kimage);
- return 0;
- }
-
-@@ -33,13 +49,18 @@ machine_kexec_cleanup(struct kimage *kim
- void
- machine_shutdown(void)
- {
-+ if (_machine_kexec_shutdown)
-+ _machine_kexec_shutdown();
- }
-
- void
- machine_crash_shutdown(struct pt_regs *regs)
- {
-+ if (_machine_crash_shutdown)
-+ _machine_crash_shutdown(regs);
-+ else
-+ default_machine_crash_shutdown(regs);
- }
--
- typedef void (*noretfun_t)(void) __attribute__((noreturn));
-
- void
-@@ -63,7 +84,7 @@ machine_kexec(struct kimage *image)
- * The generic kexec code builds a page list with physical
- * addresses. they are directly accessible through KSEG0 (or
- * CKSEG0 or XPHYS if on 64bit system), hence the
-- * pys_to_virt() call.
-+ * phys_to_virt() call.
- */
- for (ptr = &image->head; (entry = *ptr) && !(entry &IND_DONE);
- ptr = (entry & IND_INDIRECTION) ?
-@@ -78,8 +99,39 @@ machine_kexec(struct kimage *image)
- */
- local_irq_disable();
-
-- printk("Will call new kernel at %08lx\n", image->start);
-- printk("Bye ...\n");
-+ printk(KERN_EMERG "Will call new kernel at %08lx\n", image->start);
-+ printk(KERN_EMERG "Bye ...\n");
- __flush_cache_all();
-- ((noretfun_t) reboot_code_buffer)();
-+#ifdef CONFIG_SMP
-+ /* All secondary cpus now may jump to kexec_wait cycle */
-+ relocated_kexec_smp_wait = (void *)(reboot_code_buffer +
-+ (kexec_smp_wait - relocate_new_kernel));
-+ smp_wmb();
-+ atomic_set(&kexec_ready_to_reboot,1);
-+#endif
-+
-+ ((noretfun_t) reboot_code_buffer)();
-+ printk(KERN_EMERG "Bye ...\n");
-+}
-+
-+/* crashkernel=[13]size at addr specifies the location to reserve for
-+ * a crash kernel. By reserving this memory we guarantee
-+ * that linux never sets it up as a DMA target.
-+ * Useful for holding code to do something appropriate
-+ * after a kernel panic.
-+ */
-+static int __init parse_crashkernel_cmdline(char *arg)
-+{
-+ unsigned long size, base;
-+ size = memparse(arg, &arg);
-+ if (*arg == '@') {
-+ base = memparse(arg+1, &arg);
-+ /* FIXME: Do I want a sanity check
-+ * to validate the memory range?
-+ */
-+ crashk_res.start = base;
-+ crashk_res.end = base + size - 1;
-+ }
-+ return 0;
- }
-+early_param("crashkernel", parse_crashkernel_cmdline);
---- a/arch/mips/kernel/relocate_kernel.S
-+++ b/arch/mips/kernel/relocate_kernel.S
-@@ -14,7 +14,13 @@
- #include <asm/stackframe.h>
- #include <asm/addrspace.h>
-
-+
- LEAF(relocate_new_kernel)
-+ PTR_L a0, arg0
-+ PTR_L a1, arg1
-+ PTR_L a2, arg2
-+ PTR_L a3, arg3
-+
- PTR_L s0, kexec_indirection_page
- PTR_L s1, kexec_start_address
-
-@@ -26,7 +32,6 @@ process_entry:
- and s3, s2, 0x1
- beq s3, zero, 1f
- and s4, s2, ~0x1 /* store destination addr in s4 */
-- move a0, s4
- b process_entry
-
- 1:
-@@ -40,6 +45,7 @@ process_entry:
- /* done page */
- and s3, s2, 0x4
- beq s3, zero, 1f
-+ nop
- b done
- 1:
- /* source page */
-@@ -56,14 +62,102 @@ copy_word:
- PTR_ADD s2, s2, SZREG
- LONG_SUB s6, s6, 1
- beq s6, zero, process_entry
-+ nop
- b copy_word
-+ nop
- b process_entry
-
- done:
-+#ifdef CONFIG_SMP
-+ /* kexec_flag reset is signal to other CPUs what kernel
-+ was moved to it's location. Note - we need relocated address
-+ of kexec_flag. */
-+
-+ bal 1f
-+ 1: move t1,ra;
-+ PTR_LA t2,1b
-+ PTR_LA t0,kexec_flag
-+ PTR_SUB t0,t0,t2;
-+ PTR_ADD t0,t1,t0;
-+ LONG_S zero,(t0)
-+#endif
-+
-+ /* Some platforms need I-cache to be flushed before
-+ * jumping to new kernel.
-+ */
-+
- /* jump to kexec_start_address */
- j s1
- END(relocate_new_kernel)
-
-+#ifdef CONFIG_SMP
-+/*
-+ * Other CPUs should wait until code is relocated and
-+ * then start at entry point.
-+ */
-+LEAF(kexec_smp_wait)
-+ PTR_L a0, s_arg0
-+ PTR_L a1, s_arg1
-+ PTR_L a2, s_arg2
-+ PTR_L a3, s_arg3
-+ PTR_L s1, kexec_start_address
-+
-+ /* Non-relocated address works for args and kexec_start_address ( old
-+ * kernel is not overwritten). But we need relocated address of
-+ * kexec_flag.
-+ */
-+
-+ bal 1f
-+1: move t1,ra;
-+ PTR_LA t2,1b
-+ PTR_LA t0,kexec_flag
-+ PTR_SUB t0,t0,t2;
-+ PTR_ADD t0,t1,t0;
-+
-+1: LONG_L s0, (t0)
-+ bne s0, zero,1b
-+
-+ j s1
-+ END(kexec_smp_wait)
-+#endif
-+
-+
-+#ifdef __mips64
-+ /* all PTR's must be aligned to 8 byte in 64-bit mode */
-+ .align 3
-+#endif
-+
-+/* All parameters to new kernel are passed in registers a0-a3.
-+ * kexec_args[0..3] are uses to prepare register values.
-+ */
-+
-+kexec_args:
-+ EXPORT(kexec_args)
-+arg0: PTR 0x0
-+arg1: PTR 0x0
-+arg2: PTR 0x0
-+arg3: PTR 0x0
-+ .size kexec_args,PTRSIZE*4
-+
-+#ifdef CONFIG_SMP
-+/*
-+ * Secondary CPUs may have different kernel parameters in
-+ * their registers a0-a3. secondary_kexec_args[0..3] are used
-+ * to prepare register values.
-+ */
-+secondary_kexec_args:
-+ EXPORT(secondary_kexec_args)
-+s_arg0: PTR 0x0
-+s_arg1: PTR 0x0
-+s_arg2: PTR 0x0
-+s_arg3: PTR 0x0
-+ .size secondary_kexec_args,PTRSIZE*4
-+kexec_flag:
-+ LONG 0x1
-+
-+#endif
-+
-+
- kexec_start_address:
- EXPORT(kexec_start_address)
- PTR 0x0
---- a/arch/mips/kernel/setup.c
-+++ b/arch/mips/kernel/setup.c
-@@ -21,7 +21,7 @@
- #include <linux/console.h>
- #include <linux/pfn.h>
- #include <linux/debugfs.h>
--
-+#include <linux/kexec.h>
- #include <asm/addrspace.h>
- #include <asm/bootinfo.h>
- #include <asm/bugs.h>
-@@ -489,6 +489,11 @@ static void __init arch_mem_init(char **
- }
-
- bootmem_init();
-+#ifdef CONFIG_CRASH_DUMP
-+ if (crashk_res.start != crashk_res.end)
-+ reserve_bootmem(crashk_res.start,
-+ crashk_res.end - crashk_res.start + 1);
-+#endif
- sparse_init();
- paging_init();
- }
-@@ -543,6 +548,9 @@ static void __init resource_init(void)
- */
- request_resource(res, &code_resource);
- request_resource(res, &data_resource);
-+#ifdef CONFIG_KEXEC
-+ request_resource(res, &crashk_res);
-+#endif
- }
- }
-
---- a/arch/mips/include/asm/kexec.h
-+++ b/arch/mips/include/asm/kexec.h
-@@ -9,6 +9,8 @@
- #ifndef _MIPS_KEXEC
- # define _MIPS_KEXEC
-
-+#include <asm/stacktrace.h>
-+
- /* Maximum physical address we can use pages from */
- #define KEXEC_SOURCE_MEMORY_LIMIT (0x20000000)
- /* Maximum address we can reach in physical address mode */
-@@ -24,7 +26,24 @@
- static inline void crash_setup_regs(struct pt_regs *newregs,
- struct pt_regs *oldregs)
- {
-- /* Dummy implementation for now */
-+ if (oldregs)
-+ memcpy(newregs, oldregs, sizeof(*newregs));
-+ else
-+ prepare_frametrace(newregs);
- }
-
-+#ifdef CONFIG_KEXEC
-+struct kimage;
-+extern unsigned long kexec_args[4];
-+extern int (*_machine_kexec_prepare)(struct kimage *);
-+extern void (*_machine_kexec_shutdown)(void);
-+extern void (*_machine_crash_shutdown)(struct pt_regs *regs);
-+extern void default_machine_crash_shutdown(struct pt_regs *regs);
-+#ifdef CONFIG_SMP
-+extern const unsigned char kexec_smp_wait[];
-+extern unsigned long secondary_kexec_args[4];
-+extern void (*relocated_kexec_smp_wait) (void *);
-+extern atomic_t kexec_ready_to_reboot;
-+#endif
-+#endif
- #endif /* !_MIPS_KEXEC */
projects / openwrt / openwrt.git / blobdiff