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Message-Id: <ACB9BDFABD971indou.takao@jp.fujitsu.com>
Date: Tue, 14 Dec 2010 17:38:47 -0500
From: Takao Indoh <indou.takao@...fujitsu.com>
To: Kenji Kaneshige <kaneshige.kenji@...fujitsu.com>
Cc: linux-kernel@...r.kernel.org, kexec@...ts.infradead.org,
ebiederm@...ssion.com, tglx@...utronix.de, mingo@...hat.com,
hpa@...or.com, vgoyal@...hat.com, nhorman@...driver.com,
horms@...ge.net.au
Subject: Re: [PATCH v2][EFI] Run EFI in physical mode
On Tue, 14 Dec 2010 12:43:58 +0900, Kenji Kaneshige wrote:
>Hi,
>
>I tested this patch on the system that has large amount of memory (1TB),
>and I encountered the immediate system reset problem that happens every
>time I modify the EFI boot entry using efibootmgr command. It seems that
>triple fault happens due to the incorrect page table setup.
>
>> +void __init efi_pagetable_init(void)
>> +{
>(snip.)
>> + pgd = efi_pgd + pgd_index(PAGE_OFFSET);
>> + set_pgd(pgd, *pgd_offset_k(PAGE_OFFSET));
>> + pgd = efi_pgd + pgd_index(__START_KERNEL_map);
>> + set_pgd(pgd, *pgd_offset_k(__START_KERNEL_map));
>> +}
>
>Maybe we need to map whole kernel address space. The problem doesn't
>happen by modifying as follows.
>
> clone_pgd_range(efi_pgd + KERNEL_PGD_BOUNDARY,
> swapper_pg_dir + KERNEL_PGD_BOUNDARY,
>KERNEL_PGD_PTRS);
Besides this bug, I'm thinking that we need global TLB flush after
restoring cr3 because EFI code page is mapped with PAGE_KERNEL_EXEC.
void efi_call_phys_epilog_in_physmode(void)
{
write_cr3(get_cpu_var(save_cr3));
+ if (cpu_has_pge)
+ __flush_tlb_global();
local_irq_restore(get_cpu_var(efi_flags));
}
Somethinkg like this. Anybody comments?
Thanks,
Takao Indoh
>
>Regards,
>Kenji Kaneshige
>
>
>
>(2010/08/17 8:07), Takao Indoh wrote:
>> Hi all,
>>
>> Thanks for many comments. I just changed some variables according to
>> Huang's comment.
>>
>> On Mon, 16 Aug 2010 09:43:56 +0800, huang ying wrote:
>>> efi_flags and save_cr3 should be per-CPU, because they now will be
>>> used after SMP is enabled.
>>
>> Ok, what I should do next is:
>>
>> - x86 support
>> As I wrote, I don't have x86 machine where EFI works. Any
>> volunteer?
>> - ia64 support
>> I'm not sure we should do this, but I'll try if we need.
>> - Using common page tables instead of EFI own page table
>> Now I'm checking the thread below...
>> http://marc.info/?i=1280940316-7966-1-git-send-email-bp@amd64.org
>>
>>
>> Signed-off-by: Takao Indoh<indou.takao@...fujitsu.com>
>> ---
>> arch/x86/include/asm/efi.h | 3
>> arch/x86/kernel/efi.c | 142 ++++++++++++++++++++++++++++++++++-
>> arch/x86/kernel/efi_32.c | 4
>> arch/x86/kernel/efi_64.c | 96 ++++++++++++++++++++++-
>> include/linux/efi.h | 1
>> include/linux/init.h | 1
>> init/main.c | 16 +++
>> 7 files changed, 256 insertions(+), 7 deletions(-)
>>
>> diff -Nurp linux-2.6.35.org/arch/x86/include/asm/efi.h linux-2.6.35/arch/
>> x86/include/asm/efi.h
>> --- linux-2.6.35.org/arch/x86/include/asm/efi.h 2010-08-16 17:45:06.
>> 547622377 -0400
>> +++ linux-2.6.35/arch/x86/include/asm/efi.h 2010-08-16 17:45:39.021626213
>> -0400
>> @@ -93,6 +93,9 @@ extern int add_efi_memmap;
>> extern void efi_reserve_early(void);
>> extern void efi_call_phys_prelog(void);
>> extern void efi_call_phys_epilog(void);
>> +extern void efi_call_phys_prelog_in_physmode(void);
>> +extern void efi_call_phys_epilog_in_physmode(void);
>> +extern void efi_pagetable_init(void);
>>
>> #ifndef CONFIG_EFI
>> /*
>> diff -Nurp linux-2.6.35.org/arch/x86/kernel/efi.c linux-2.6.35/arch/x86/
>> kernel/efi.c
>> --- linux-2.6.35.org/arch/x86/kernel/efi.c 2010-08-16 17:45:06.500622377
>> -0400
>> +++ linux-2.6.35/arch/x86/kernel/efi.c 2010-08-16 17:45:39.022633025
>> -0400
>> @@ -57,6 +57,7 @@ struct efi_memory_map memmap;
>>
>> static struct efi efi_phys __initdata;
>> static efi_system_table_t efi_systab __initdata;
>> +static efi_runtime_services_t phys_runtime;
>>
>> static int __init setup_noefi(char *arg)
>> {
>> @@ -171,7 +172,7 @@ static efi_status_t __init phys_efi_set_
>> return status;
>> }
>>
>> -static efi_status_t __init phys_efi_get_time(efi_time_t *tm,
>> +static efi_status_t __init phys_efi_get_time_early(efi_time_t *tm,
>> efi_time_cap_t *tc)
>> {
>> efi_status_t status;
>> @@ -182,6 +183,112 @@ static efi_status_t __init phys_efi_get_
>> return status;
>> }
>>
>> +static efi_status_t phys_efi_get_time(efi_time_t *tm,
>> + efi_time_cap_t *tc)
>> +{
>> + efi_status_t status;
>> +
>> + efi_call_phys_prelog_in_physmode();
>> + status = efi_call_phys2((void*)phys_runtime.get_time, tm, tc);
>> + efi_call_phys_epilog_in_physmode();
>> + return status;
>> +}
>> +
>> +static efi_status_t __init phys_efi_set_time(efi_time_t *tm)
>> +{
>> + efi_status_t status;
>> +
>> + efi_call_phys_prelog_in_physmode();
>> + status = efi_call_phys1((void*)phys_runtime.set_time, tm);
>> + efi_call_phys_epilog_in_physmode();
>> + return status;
>> +}
>> +
>> +static efi_status_t phys_efi_get_wakeup_time(efi_bool_t *enabled,
>> + efi_bool_t *pending,
>> + efi_time_t *tm)
>> +{
>> + efi_status_t status;
>> +
>> + efi_call_phys_prelog_in_physmode();
>> + status = efi_call_phys3((void*)phys_runtime.get_wakeup_time, enabled,
>> + pending, tm);
>> + efi_call_phys_epilog_in_physmode();
>> + return status;
>> +}
>> +
>> +static efi_status_t phys_efi_set_wakeup_time(efi_bool_t enabled,
>> efi_time_t *tm)
>> +{
>> + efi_status_t status;
>> + efi_call_phys_prelog_in_physmode();
>> + status = efi_call_phys2((void*)phys_runtime.set_wakeup_time, enabled,
>> + tm);
>> + efi_call_phys_epilog_in_physmode();
>> + return status;
>> +}
>> +
>> +static efi_status_t phys_efi_get_variable(efi_char16_t *name,
>> + efi_guid_t *vendor,
>> + u32 *attr,
>> + unsigned long *data_size,
>> + void *data)
>> +{
>> + efi_status_t status;
>> + efi_call_phys_prelog_in_physmode();
>> + status = efi_call_phys5((void*)phys_runtime.get_variable, name, vendor,
>> + attr, data_size, data);
>> + efi_call_phys_epilog_in_physmode();
>> + return status;
>> +}
>> +
>> +static efi_status_t phys_efi_get_next_variable(unsigned long *name_size,
>> + efi_char16_t *name,
>> + efi_guid_t *vendor)
>> +{
>> + efi_status_t status;
>> +
>> + efi_call_phys_prelog_in_physmode();
>> + status = efi_call_phys3((void*)phys_runtime.get_next_variable,
>> + name_size, name, vendor);
>> + efi_call_phys_epilog_in_physmode();
>> + return status;
>> +}
>> +
>> +static efi_status_t phys_efi_set_variable(efi_char16_t *name,
>> + efi_guid_t *vendor,
>> + unsigned long attr,
>> + unsigned long data_size,
>> + void *data)
>> +{
>> + efi_status_t status;
>> + efi_call_phys_prelog_in_physmode();
>> + status = efi_call_phys5((void*)phys_runtime.set_variable, name,
>> + vendor, attr, data_size, data);
>> + efi_call_phys_epilog_in_physmode();
>> + return status;
>> +}
>> +
>> +static efi_status_t phys_efi_get_next_high_mono_count(u32 *count)
>> +{
>> + efi_status_t status;
>> + efi_call_phys_prelog_in_physmode();
>> + status = efi_call_phys1((void*)phys_runtime.get_next_high_mono_count,
>> + count);
>> + efi_call_phys_epilog_in_physmode();
>> + return status;
>> +}
>> +
>> +static void phys_efi_reset_system(int reset_type,
>> + efi_status_t status,
>> + unsigned long data_size,
>> + efi_char16_t *data)
>> +{
>> + efi_call_phys_prelog_in_physmode();
>> + efi_call_phys4((void*)phys_runtime.reset_system, reset_type, status,
>> + data_size, data);
>> + efi_call_phys_epilog_in_physmode();
>> +}
>> +
>> int efi_set_rtc_mmss(unsigned long nowtime)
>> {
>> int real_seconds, real_minutes;
>> @@ -434,7 +541,9 @@ void __init efi_init(void)
>> * Make efi_get_time can be called before entering
>> * virtual mode.
>> */
>> - efi.get_time = phys_efi_get_time;
>> + efi.get_time = phys_efi_get_time_early;
>> +
>> + memcpy(&phys_runtime, runtime, sizeof(
>> efi_runtime_services_t));
>> } else
>> printk(KERN_ERR "Could not map the EFI runtime service "
>> "table!\n");
>> @@ -465,6 +574,14 @@ void __init efi_init(void)
>> #if EFI_DEBUG
>> print_efi_memmap();
>> #endif
>> +
>> +#ifndef CONFIG_X86_64
>> + /*
>> + * Only x86_64 supports physical mode as of now. Use virtual mode
>> + * forcibly.
>> + */
>> + usevirtefi = 1;
>> +#endif
>> }
>>
>> static void __init runtime_code_page_mkexec(void)
>> @@ -578,6 +695,27 @@ void __init efi_enter_virtual_mode(void)
>> memmap.map = NULL;
>> }
>>
>> +void __init efi_setup_physical_mode(void)
>> +{
>> +#ifdef CONFIG_X86_64
>> + efi_pagetable_init();
>> +#endif
>> + efi.get_time = phys_efi_get_time;
>> + efi.set_time = phys_efi_set_time;
>> + efi.get_wakeup_time = phys_efi_get_wakeup_time;
>> + efi.set_wakeup_time = phys_efi_set_wakeup_time;
>> + efi.get_variable = phys_efi_get_variable;
>> + efi.get_next_variable = phys_efi_get_next_variable;
>> + efi.set_variable = phys_efi_set_variable;
>> + efi.get_next_high_mono_count =
>> + phys_efi_get_next_high_mono_count;
>> + efi.reset_system = phys_efi_reset_system;
>> + efi.set_virtual_address_map = NULL; /* Not needed */
>> +
>> + early_iounmap(memmap.map, memmap.nr_map * memmap.desc_size);
>> + memmap.map = NULL;
>> +}
>> +
>> /*
>> * Convenience functions to obtain memory types and attributes
>> */
>> diff -Nurp linux-2.6.35.org/arch/x86/kernel/efi_32.c linux-2.6.35/arch/x86/
>> kernel/efi_32.c
>> --- linux-2.6.35.org/arch/x86/kernel/efi_32.c 2010-08-16 17:45:06.
>> 522621888 -0400
>> +++ linux-2.6.35/arch/x86/kernel/efi_32.c 2010-08-16 17:45:39.022633025
>> -0400
>> @@ -110,3 +110,7 @@ void efi_call_phys_epilog(void)
>>
>> local_irq_restore(efi_rt_eflags);
>> }
>> +
>> +void efi_call_phys_prelog_in_physmode(void) { /* Not supported */ }
>> +void efi_call_phys_epilog_in_physmode(void) { /* Not supported */ }
>> +
>> diff -Nurp linux-2.6.35.org/arch/x86/kernel/efi_64.c linux-2.6.35/arch/x86/
>> kernel/efi_64.c
>> --- linux-2.6.35.org/arch/x86/kernel/efi_64.c 2010-08-16 17:45:06.
>> 499622447 -0400
>> +++ linux-2.6.35/arch/x86/kernel/efi_64.c 2010-08-16 17:45:39.023650384
>> -0400
>> @@ -39,7 +39,9 @@
>> #include<asm/fixmap.h>
>>
>> static pgd_t save_pgd __initdata;
>> -static unsigned long efi_flags __initdata;
>> +static DEFINE_PER_CPU(unsigned long, efi_flags);
>> +static DEFINE_PER_CPU(unsigned long, save_cr3);
>> +static pgd_t efi_pgd[PTRS_PER_PGD] __page_aligned_bss;
>>
>> static void __init early_mapping_set_exec(unsigned long start,
>> unsigned long end,
>> @@ -80,7 +82,7 @@ void __init efi_call_phys_prelog(void)
>> unsigned long vaddress;
>>
>> early_runtime_code_mapping_set_exec(1);
>> - local_irq_save(efi_flags);
>> + local_irq_save(get_cpu_var(efi_flags));
>> vaddress = (unsigned long)__va(0x0UL);
>> save_pgd = *pgd_offset_k(0x0UL);
>> set_pgd(pgd_offset_k(0x0UL), *pgd_offset_k(vaddress));
>> @@ -94,10 +96,23 @@ void __init efi_call_phys_epilog(void)
>> */
>> set_pgd(pgd_offset_k(0x0UL), save_pgd);
>> __flush_tlb_all();
>> - local_irq_restore(efi_flags);
>> + local_irq_restore(get_cpu_var(efi_flags));
>> early_runtime_code_mapping_set_exec(0);
>> }
>>
>> +void efi_call_phys_prelog_in_physmode(void)
>> +{
>> + local_irq_save(get_cpu_var(efi_flags));
>> + get_cpu_var(save_cr3)= read_cr3();
>> + write_cr3(virt_to_phys(efi_pgd));
>> +}
>> +
>> +void efi_call_phys_epilog_in_physmode(void)
>> +{
>> + write_cr3(get_cpu_var(save_cr3));
>> + local_irq_restore(get_cpu_var(efi_flags));
>> +}
>> +
>> void __iomem *__init efi_ioremap(unsigned long phys_addr, unsigned long
>> size,
>> u32 type)
>> {
>> @@ -112,3 +127,78 @@ void __iomem *__init efi_ioremap(unsigne
>>
>> return (void __iomem *)__va(phys_addr);
>> }
>> +
>> +static pud_t *fill_pud(pgd_t *pgd, unsigned long vaddr)
>> +{
>> + if (pgd_none(*pgd)) {
>> + pud_t *pud = (pud_t *)get_zeroed_page(GFP_ATOMIC);
>> + set_pgd(pgd, __pgd(_PAGE_TABLE | __pa(pud)));
>> + if (pud != pud_offset(pgd, 0))
>> + printk(KERN_ERR "EFI PAGETABLE BUG #00! %p<-> %p\n",
>> + pud, pud_offset(pgd, 0));
>> + }
>> + return pud_offset(pgd, vaddr);
>> +}
>> +
>> +static pmd_t *fill_pmd(pud_t *pud, unsigned long vaddr)
>> +{
>> + if (pud_none(*pud)) {
>> + pmd_t *pmd = (pmd_t *)get_zeroed_page(GFP_ATOMIC);
>> + set_pud(pud, __pud(_PAGE_TABLE | __pa(pmd)));
>> + if (pmd != pmd_offset(pud, 0))
>> + printk(KERN_ERR "EFI PAGETABLE BUG #01! %p<-> %p\n",
>> + pmd, pmd_offset(pud, 0));
>> + }
>> + return pmd_offset(pud, vaddr);
>> +}
>> +
>> +static pte_t *fill_pte(pmd_t *pmd, unsigned long vaddr)
>> +{
>> + if (pmd_none(*pmd)) {
>> + pte_t *pte = (pte_t *)get_zeroed_page(GFP_ATOMIC);
>> + set_pmd(pmd, __pmd(_PAGE_TABLE | __pa(pte)));
>> + if (pte != pte_offset_kernel(pmd, 0))
>> + printk(KERN_ERR "EFI PAGETABLE BUG #02!\n");
>> + }
>> + return pte_offset_kernel(pmd, vaddr);
>> +}
>> +
>> +void __init efi_pagetable_init(void)
>> +{
>> + efi_memory_desc_t *md;
>> + unsigned long size;
>> + u64 start_pfn, end_pfn, pfn, vaddr;
>> + void *p;
>> + pgd_t *pgd;
>> + pud_t *pud;
>> + pmd_t *pmd;
>> + pte_t *pte;
>> +
>> + memset(efi_pgd, 0, sizeof(efi_pgd));
>> + for (p = memmap.map; p< memmap.map_end; p += memmap.desc_size) {
>> + md = p;
>> + if (!(md->type& EFI_RUNTIME_SERVICES_CODE)&&
>> + !(md->type& EFI_RUNTIME_SERVICES_DATA))
>> + continue;
>> +
>> + start_pfn = md->phys_addr>> PAGE_SHIFT;
>> + size = md->num_pages<< EFI_PAGE_SHIFT;
>> + end_pfn = PFN_UP(md->phys_addr + size);
>> +
>> + for (pfn = start_pfn; pfn<= end_pfn; pfn++) {
>> + vaddr = pfn<< PAGE_SHIFT;
>> + pgd = efi_pgd + pgd_index(vaddr);
>> + pud = fill_pud(pgd, vaddr);
>> + pmd = fill_pmd(pud, vaddr);
>> + pte = fill_pte(pmd, vaddr);
>> + if (md->type& EFI_RUNTIME_SERVICES_CODE)
>> + set_pte(pte, pfn_pte(pfn, PAGE_KERNEL_EXEC));
>> + else
>> + set_pte(pte, pfn_pte(pfn, PAGE_KERNEL));
>> + }
>> + }
>> + pgd = efi_pgd + pgd_index(PAGE_OFFSET);
>> + set_pgd(pgd, *pgd_offset_k(PAGE_OFFSET));
>> + pgd = efi_pgd + pgd_index(__START_KERNEL_map);
>> + set_pgd(pgd, *pgd_offset_k(__START_KERNEL_map));
>> +}
>> diff -Nurp linux-2.6.35.org/include/linux/efi.h linux-2.6.35/include/linux/
>> efi.h
>> --- linux-2.6.35.org/include/linux/efi.h 2010-08-16 17:45:06.015622308
>> -0400
>> +++ linux-2.6.35/include/linux/efi.h 2010-08-16 17:45:39.023650384 -0400
>> @@ -290,6 +290,7 @@ extern void efi_map_pal_code (void);
>> extern void efi_memmap_walk (efi_freemem_callback_t callback, void *arg);
>> extern void efi_gettimeofday (struct timespec *ts);
>> extern void efi_enter_virtual_mode (void); /* switch EFI to virtual mode,
>> if possible */
>> +extern void efi_setup_physical_mode(void);
>> extern u64 efi_get_iobase (void);
>> extern u32 efi_mem_type (unsigned long phys_addr);
>> extern u64 efi_mem_attributes (unsigned long phys_addr);
>> diff -Nurp linux-2.6.35.org/include/linux/init.h linux-2.6.35/include/linux
>> /init.h
>> --- linux-2.6.35.org/include/linux/init.h 2010-08-16 17:45:06.059622448
>> -0400
>> +++ linux-2.6.35/include/linux/init.h 2010-08-16 17:45:39.024651054
>> -0400
>> @@ -142,6 +142,7 @@ extern int do_one_initcall(initcall_t fn
>> extern char __initdata boot_command_line[];
>> extern char *saved_command_line;
>> extern unsigned int reset_devices;
>> +extern unsigned int usevirtefi;
>>
>> /* used by init/main.c */
>> void setup_arch(char **);
>> diff -Nurp linux-2.6.35.org/init/main.c linux-2.6.35/init/main.c
>> --- linux-2.6.35.org/init/main.c 2010-08-16 17:45:05.729683838 -0400
>> +++ linux-2.6.35/init/main.c 2010-08-16 17:45:39.025650051 -0400
>> @@ -200,6 +200,14 @@ static int __init set_reset_devices(char
>>
>> __setup("reset_devices", set_reset_devices);
>>
>> +unsigned int usevirtefi;
>> +static int __init set_virt_efi(char *str)
>> +{
>> + usevirtefi = 1;
>> + return 1;
>> +}
>> +__setup("virtefi", set_virt_efi);
>> +
>> static char * argv_init[MAX_INIT_ARGS+2] = { "init", NULL, };
>> char * envp_init[MAX_INIT_ENVS+2] = { "HOME=/", "TERM=linux", NULL, };
>> static const char *panic_later, *panic_param;
>> @@ -676,8 +684,12 @@ asmlinkage void __init start_kernel(void
>> pidmap_init();
>> anon_vma_init();
>> #ifdef CONFIG_X86
>> - if (efi_enabled)
>> - efi_enter_virtual_mode();
>> + if (efi_enabled) {
>> + if (usevirtefi)
>> + efi_enter_virtual_mode();
>> + else
>> + efi_setup_physical_mode();
>> + }
>> #endif
>> thread_info_cache_init();
>> cred_init();
>>
>> --
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