Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932214AbbG1M25 (ORCPT ); Tue, 28 Jul 2015 08:28:57 -0400 Received: from atrey.karlin.mff.cuni.cz ([195.113.26.193]:43281 "EHLO atrey.karlin.mff.cuni.cz" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751874AbbG1M2z (ORCPT ); Tue, 28 Jul 2015 08:28:55 -0400 Date: Tue, 28 Jul 2015 14:28:53 +0200 From: Pavel Machek To: "Lee, Chun-Yi" Cc: linux-kernel@vger.kernel.org, linux-efi@vger.kernel.org, linux-pm@vger.kernel.org, "Rafael J. Wysocki" , Matthew Garrett , Len Brown , Josh Boyer , Vojtech Pavlik , Matt Fleming , Jiri Kosina , "H. Peter Anvin" , "Lee, Chun-Yi" Subject: Re: [RFC PATCH 05/16] x86/efi: Get entropy through EFI random number generator protocol Message-ID: <20150728122853.GB12681@amd> References: <1437056730-15247-1-git-send-email-jlee@suse.com> <1437056730-15247-6-git-send-email-jlee@suse.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1437056730-15247-6-git-send-email-jlee@suse.com> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4079 Lines: 131 On Thu 2015-07-16 22:25:19, Lee, Chun-Yi wrote: > To grab random numbers through EFI protocol as one of the entropies > source of swsusp key, this patch adds the logic for accessing EFI RNG > (random number generator) protocol that's introduced since UEFI 2.4. > > Signed-off-by: Lee, Chun-Yi > --- > arch/x86/boot/compressed/efi_random.c | 193 ++++++++++++++++++++++++++++++++++ > include/linux/efi.h | 46 ++++++++ > 2 files changed, 239 insertions(+) > > diff --git a/arch/x86/boot/compressed/efi_random.c b/arch/x86/boot/compressed/efi_random.c > index bdb2d46..1f5c63d 100644 > --- a/arch/x86/boot/compressed/efi_random.c > +++ b/arch/x86/boot/compressed/efi_random.c > @@ -2,6 +2,191 @@ > > #include > #include > +#include > + > +static efi_status_t efi_locate_rng(efi_system_table_t *sys_table, > + void ***rng_handle) > +{ > + efi_guid_t rng_proto = EFI_RNG_PROTOCOL_GUID; > + unsigned long size = 0; > + efi_status_t status; > + > + status = efi_call_early(locate_handle, > + EFI_LOCATE_BY_PROTOCOL, > + &rng_proto, NULL, &size, *rng_handle); > + > + if (status == EFI_BUFFER_TOO_SMALL) { > + status = efi_call_early(allocate_pool, > + EFI_LOADER_DATA, > + size, (void **)rng_handle); > + > + if (status != EFI_SUCCESS) { > + efi_printk(sys_table, " Failed to alloc mem for rng_handle"); > + return status; > + } > + > + status = efi_call_early(locate_handle, > + EFI_LOCATE_BY_PROTOCOL, &rng_proto, > + NULL, &size, *rng_handle); > + } > + > + if (status != EFI_SUCCESS) { > + efi_printk(sys_table, " Failed to locateEFI_RNG_PROTOCOL"); missing \n? > + goto free_handle; You use that label exactly once, no need for goto > +static bool efi_rng_supported32(efi_system_table_t *sys_table, void **rng_handle) > +{ > + const struct efi_config *efi_early = __efi_early(); > + efi_rng_protocol_32 *rng = NULL; ...> +static bool efi_rng_supported64(efi_system_table_t *sys_table, void **rng_handle) > +{ > + const struct efi_config *efi_early = __efi_early(); > + efi_rng_protocol_64 *rng = NULL; > + efi_guid_t rng_proto = EFI_RNG_PROTOCOL_GUID; ... > +static unsigned long efi_get_rng32(efi_system_table_t *sys_table, > + void **rng_handle) > +{ > + const struct efi_config *efi_early = __efi_early(); > + efi_rng_protocol_32 *rng = NULL; > + efi_guid_t rng_proto = EFI_RNG_PROTOCOL_GUID; ... > +static unsigned long efi_get_rng64(efi_system_table_t *sys_table, > + void **rng_handle) > +{ > + const struct efi_config *efi_early = __efi_early(); > + efi_rng_protocol_64 *rng = NULL; > + efi_guid_t rng_proto = EFI_RNG_PROTOCOL_GUID; Can you do something to avoid each function having two very similar versions of these functions? > + if (status != EFI_SUCCESS) { > + efi_printk(sys_table, " Failed to get RNG value "); > + efi_printk(sys_table, efi_status_to_str(status)); Yep. You definitely have \n problems here. > --- a/include/linux/efi.h > +++ b/include/linux/efi.h > @@ -427,6 +427,16 @@ typedef struct { > #define EFI_PCI_IO_ATTRIBUTE_VGA_PALETTE_IO_16 0x20000 > #define EFI_PCI_IO_ATTRIBUTE_VGA_IO_16 0x40000 > > +typedef struct { > + u32 get_info; > + u32 get_rng; > +} efi_rng_protocol_32; > + > +typedef struct { > + u64 get_info; > + u64 get_rng; > +} efi_rng_protocol_64; We don't typedef structs usually... Make it union so you can have just one > +static inline char *efi_status_to_str(efi_status_t status) > +{ > + char *str; > + Are you sure you want this inlined? > + switch (status) { > + case EFI_SUCCESS: > + str = "EFI_SUCCESS"; > + break; Can you use macros to reduce code duplication here? Pavel -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/