| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-ID: <561AC137.9090809@redhat.com> Date: Sun, 11 Oct 2015 22:06:15 +0200 From: Laurent Vivier <lvivier@...hat.com> To: Finn Thain <fthain@...egraphics.com.au>, linux-kernel@...r.kernel.org, linux-m68k@...r.kernel.org, linuxppc-dev@...ts.ozlabs.org Subject: Re: [RFC v6 00/25] Re-use nvram module On 23/08/2015 12:41, Finn Thain wrote: > The generic NVRAM module, drivers/char/generic_nvram, implements a > /dev/nvram misc device. It is used only by 32-bit PowerPC platforms and > isn't generic enough to be more widely used. > > The RTC NVRAM module, drivers/char/nvram, also implements a /dev/nvram > misc device. It is used by x86, ARM and m68k. > > The former module cannot be used on x86, ARM or m68k because it > cannot co-exist with the latter module, partly due to the Kconfig logic. > > It is possible to modify the modules so that one kernel binary could > have either, neither or both. However, automatically loading the > appropriate module is then impossible; if both provide the > char-major-10-144 alias then the wrong module will end up being loaded. > Hence a multi-platform kernel binary needs a single generic nvram module > with alias char-major-10-144. > > Therefore, drivers/char/nvram.c should be made more generic and the > arch-specific code therein should be moved to a more appropriate > place under arch/. Also, drivers/char/generic_nvram.c should be removed > to reduce code duplication. > > In this patch series, Atari-specific code is moved from the nvram module > to arch/m68k/atari. More arch-specific code in the nvram module could > be moved, probably to arch/x86, but it is difficult to determine just > what code is relevant to ARM platforms and what code is x86-only. > > In addressing code duplication, v1 of this patch series removes three > inconsistent /dev/nvram misc device implementations. One of these, > drivers/macintosh/nvram.c is entirely unused already. The other two, > drivers/char/generic_nvram.c and the misc device implementation in > arch/powerpc/kernel/nvram_64.c, are replaced by drivers/char/nvram.c. > > A benefit of this work is better consistency -- between PPC32 and PPC64 > as well as between PPC_PMAC and MAC. This new uniformity does have > implications for userspace, that is, some error codes for some ioctl calls > become consistent on all PowerPC platforms. > > The drivers/char/nvram module becomes sufficiently generic to be useful > to other platforms and architectures, besides those with "CMOS" RTC. At the > end of this patch series the module is adopted by the m68k Mac port, which > already has PRAM access functions but lacks the /dev/nvram misc device. > > This patch series has been compile-tested for arm, m68k, powerpc and x86. > The nvram and thinkpad_acpi modules were regression tested on a ThinkPad > T43. The /dev/nvram functionality was also regression tested on a G3 > PowerMac. The nvram module was also tested on a PowerBook 520, Quadra 650 > and Atari Falcon. AFAIK, no testing has been done on PPC64 as yet. For PPC64, tested on a PowerMac G5 (PowerMac11,2), kernel 4.3.0-rc4 with nvram tools 1.2.24 (Fedora 22 ppc64). Tested-by: Laurent Vivier <lvivier@...hat.com> Tests done: # modinfo nvram filename: /lib/modules/4.3.0-rc4+/kernel/drivers/char/nvram.ko alias: devname:nvram alias: char-major-10-144 license: GPL depends: intree: Y vermagic: 4.3.0-rc4+ SMP mod_unload # modprobe nvram [ 364.655577] Non-volatile memory driver v1.3 # nvram --partitions # Sig Chk Len Name 0 5a 82 0002 nvram 1 5f 45 003e system 2 70 bd 00c1 common 3 a0 1e 0052 APL,MacOS75 4 a1 15 0081 APL,OSXPanic 5 7f 45 002c wwwwwwwwwwww # nvram --dump "nvram" 0x00000000 5a820002 6e767261 6d000000 00000000 |Z...nvram.......| 0x00000010 cae8613d 000001c9 00000000 00000000 |..a=............| # nvram --print-config=boot-volume 1 # nvram --update-config=boot-volume=6 # rmmod nvram # nvram --print-config=boot-volume 6 # reboot # nvram --print-config=boot-volume 6 > Changes since v1: > - Minor changes to patches 7, 15 and 20 as described in commit logs. > - Revised patches 21 and 24 to address comments from Geert. > > Changes since v2: > - Dropped patch 1, "macintosh/nvram: Remove as unused", because it has > since been merged. > - Inserted a new patch, "m68k/mac: Use macros for RTC accesses not > magic numbers". > - Revised patches 21 and 23 to address comments from Geert. > > Changes since v3: > - Split the patch, "m68k/atari: Move Atari-specific code out of > drivers/char/nvram.c", as suggested by Geert. > - Revised patches 11 and 25 to address comments from Geert. > - Minor change to patch 21 as described in commit log. > > Changes since v4: > - Split the patch, "powerpc, fbdev: Use arch_nvram_ops methods instead > of nvram_read_byte() and nvram_write_byte()", so as to separately address > inconsistent use of Kconfig symbols in PowerMac fbdev drivers. > - Fix possible git bisect build failure with CONFIG_PPC_PMAC=n. > > Changes since v5: > - Dropped patch 2, "char/nvram: Use bitwise OR to obtain Atari video mode > data", since it has been added to Greg Kroah-Hartman's char-misc-next queue. > - In patch 15, error codes from the IOC_NVRAM_GET_OFFSET ioctl are now > consistent with the old generic_nvram module. > > --- > arch/m68k/Kconfig | 3 > arch/m68k/Kconfig.machine | 2 > arch/m68k/atari/Makefile | 2 > arch/m68k/atari/nvram.c | 291 +++++++++++ > arch/m68k/include/asm/atarihw.h | 6 > arch/m68k/include/asm/macintosh.h | 4 > arch/m68k/kernel/setup_mm.c | 100 +++ > arch/m68k/mac/misc.c | 207 +++++--- > arch/powerpc/Kconfig | 5 > arch/powerpc/include/asm/nvram.h | 9 > arch/powerpc/kernel/nvram_64.c | 203 +------ > arch/powerpc/kernel/setup_32.c | 27 - > arch/powerpc/platforms/chrp/Makefile | 2 > arch/powerpc/platforms/chrp/nvram.c | 14 > arch/powerpc/platforms/chrp/setup.c | 2 > arch/powerpc/platforms/powermac/Makefile | 5 > arch/powerpc/platforms/powermac/nvram.c | 9 > arch/powerpc/platforms/powermac/setup.c | 3 > arch/powerpc/platforms/pseries/nvram.c | 2 > drivers/char/Kconfig | 13 > drivers/char/Makefile | 6 > drivers/char/generic_nvram.c | 174 ------ > drivers/char/nvram.c | 742 ++++++++++++----------------- > drivers/platform/x86/thinkpad_acpi.c | 20 > drivers/scsi/Kconfig | 6 > drivers/scsi/atari_scsi.c | 16 > drivers/video/fbdev/Kconfig | 2 > drivers/video/fbdev/controlfb.c | 4 > drivers/video/fbdev/imsttfb.c | 17 > drivers/video/fbdev/matrox/matroxfb_base.c | 6 > drivers/video/fbdev/platinumfb.c | 4 > drivers/video/fbdev/valkyriefb.c | 18 > include/linux/nvram.h | 23 > include/uapi/linux/pmu.h | 2 > 34 files changed, 998 insertions(+), 951 deletions(-) > > > > > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@...r.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@...r.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists