From f4892c68ecc1cf45e41a78820dd2eebccc945b66 Mon Sep 17 00:00:00 2001 From: Hari Bathini Date: Thu, 7 Nov 2024 11:28:16 +0530 Subject: [PATCH] powerpc/fadump: allocate memory for additional parameters early Memory for passing additional parameters to fadump capture kernel is allocated during subsys_initcall level, using memblock. But as slab is already available by this time, allocation happens via the buddy allocator. This may work for radix MMU but is likely to fail in most cases for hash MMU as hash MMU needs this memory in the first memory block for it to be accessible in real mode in the capture kernel (second boot). So, allocate memory for additional parameters area as soon as MMU mode is obvious. Fixes: 683eab94da75 ("powerpc/fadump: setup additional parameters for dump capture kernel") Reported-by: Venkat Rao Bagalkote Closes: https://lore.kernel.org/lkml/a70e4064-a040-447b-8556-1fd02f19383d@linux.vnet.ibm.com/T/#u Signed-off-by: Hari Bathini Signed-off-by: Sourabh Jain Tested-by: Venkat Rao Bagalkote Signed-off-by: Michael Ellerman Link: https://patch.msgid.link/20241107055817.489795-1-sourabhjain@linux.ibm.com --- arch/powerpc/include/asm/fadump.h | 2 ++ arch/powerpc/kernel/fadump.c | 15 ++++++++++----- arch/powerpc/kernel/prom.c | 3 +++ 3 files changed, 15 insertions(+), 5 deletions(-) diff --git a/arch/powerpc/include/asm/fadump.h b/arch/powerpc/include/asm/fadump.h index 3638f04447f59..a48f54dde4f65 100644 --- a/arch/powerpc/include/asm/fadump.h +++ b/arch/powerpc/include/asm/fadump.h @@ -19,6 +19,7 @@ extern int is_fadump_active(void); extern int should_fadump_crash(void); extern void crash_fadump(struct pt_regs *, const char *); extern void fadump_cleanup(void); +void fadump_setup_param_area(void); extern void fadump_append_bootargs(void); #else /* CONFIG_FA_DUMP */ @@ -26,6 +27,7 @@ static inline int is_fadump_active(void) { return 0; } static inline int should_fadump_crash(void) { return 0; } static inline void crash_fadump(struct pt_regs *regs, const char *str) { } static inline void fadump_cleanup(void) { } +static inline void fadump_setup_param_area(void) { } static inline void fadump_append_bootargs(void) { } #endif /* !CONFIG_FA_DUMP */ diff --git a/arch/powerpc/kernel/fadump.c b/arch/powerpc/kernel/fadump.c index c42f89862893e..5583017bbfbce 100644 --- a/arch/powerpc/kernel/fadump.c +++ b/arch/powerpc/kernel/fadump.c @@ -1587,6 +1587,12 @@ static void __init fadump_init_files(void) return; } + if (fw_dump.param_area) { + rc = sysfs_create_file(fadump_kobj, &bootargs_append_attr.attr); + if (rc) + pr_err("unable to create bootargs_append sysfs file (%d)\n", rc); + } + debugfs_create_file("fadump_region", 0444, arch_debugfs_dir, NULL, &fadump_region_fops); @@ -1741,7 +1747,7 @@ err_out: * Reserve memory to store additional parameters to be passed * for fadump/capture kernel. */ -static void __init fadump_setup_param_area(void) +void __init fadump_setup_param_area(void) { phys_addr_t range_start, range_end; @@ -1749,7 +1755,7 @@ static void __init fadump_setup_param_area(void) return; /* This memory can't be used by PFW or bootloader as it is shared across kernels */ - if (radix_enabled()) { + if (early_radix_enabled()) { /* * Anywhere in the upper half should be good enough as all memory * is accessible in real mode. @@ -1777,12 +1783,12 @@ static void __init fadump_setup_param_area(void) COMMAND_LINE_SIZE, range_start, range_end); - if (!fw_dump.param_area || sysfs_create_file(fadump_kobj, &bootargs_append_attr.attr)) { + if (!fw_dump.param_area) { pr_warn("WARNING: Could not setup area to pass additional parameters!\n"); return; } - memset(phys_to_virt(fw_dump.param_area), 0, COMMAND_LINE_SIZE); + memset((void *)fw_dump.param_area, 0, COMMAND_LINE_SIZE); } /* @@ -1808,7 +1814,6 @@ int __init setup_fadump(void) } /* Initialize the kernel dump memory structure and register with f/w */ else if (fw_dump.reserve_dump_area_size) { - fadump_setup_param_area(); fw_dump.ops->fadump_init_mem_struct(&fw_dump); register_fadump(); } diff --git a/arch/powerpc/kernel/prom.c b/arch/powerpc/kernel/prom.c index 0be07ed407c70..47db1b1aef254 100644 --- a/arch/powerpc/kernel/prom.c +++ b/arch/powerpc/kernel/prom.c @@ -908,6 +908,9 @@ void __init early_init_devtree(void *params) mmu_early_init_devtree(); + /* Setup param area for passing additional parameters to fadump capture kernel. */ + fadump_setup_param_area(); + #ifdef CONFIG_PPC_POWERNV /* Scan and build the list of machine check recoverable ranges */ of_scan_flat_dt(early_init_dt_scan_recoverable_ranges, NULL); -- 2.39.5