Hi, On 14-10-2019 11:11, Luis Chamberlain wrote:
On Fri, Oct 04, 2019 at 04:50:49PM +0200, Hans de Goede wrote:diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c index 8d3e778e988b..abba49c4c46d 100644 --- a/drivers/firmware/efi/efi.c +++ b/drivers/firmware/efi/efi.c @@ -314,6 +315,55 @@ static __init int efivar_ssdt_load(void) static inline int efivar_ssdt_load(void) { return 0; } #endif+#ifdef CONFIG_DEBUG_FS+ +#define EFI_DEBUGFS_MAX_BLOBS 32 + +static struct debugfs_blob_wrapper debugfs_blob[EFI_DEBUGFS_MAX_BLOBS]; + +static void __init efi_debugfs_init(void) +{ + struct dentry *efi_debugfs; + efi_memory_desc_t *md; + char name[32]; + int type_count[EFI_BOOT_SERVICES_DATA + 1] = {}; + int i = 0; + + efi_debugfs = debugfs_create_dir("efi", NULL); + if (IS_ERR_OR_NULL(efi_debugfs)) + return; + + for_each_efi_memory_desc(md) { + switch (md->type) { + case EFI_BOOT_SERVICES_CODE: + snprintf(name, sizeof(name), "boot_services_code%d", + type_count[md->type]++); + break; + case EFI_BOOT_SERVICES_DATA: + snprintf(name, sizeof(name), "boot_services_data%d", + type_count[md->type]++); + break; + default: + continue; + } + + debugfs_blob[i].size = md->num_pages << EFI_PAGE_SHIFT; + debugfs_blob[i].data = memremap(md->phys_addr, + debugfs_blob[i].size, + MEMREMAP_WB); + if (!debugfs_blob[i].data) + continue; + + debugfs_create_blob(name, 0400, efi_debugfs, &debugfs_blob[i]); + i++; + if (i == EFI_DEBUGFS_MAX_BLOBS) + break;Why do we silently ignore more entries ?
A valid remark, I agree that adding a pr_warn_once here would be good I will do so for the next version.
And could documentation be added for ways in which this could be used in practice?
I can write a little how to use this to get an embedded firmware, I will add this to firmware/fallback-mechanisms.rst for the next version. Regards, Hans
