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Joel Stanley 960e300298 powerpc/Makefile: Fix PPC_BOOK3S_64 ASFLAGS 
Ever since commit 15a3204d24 ("powerpc/64s: Set assembler machine type
to POWER4") we force -mpower4 to be passed to the assembler
irrespective of the CFLAGS used (for Book3s 64).

When building a powerpc64 kernel with clang, clang will not add -many
to the assembler flags, so any instructions that the compiler has
generated that are not available on power4 will cause an error:

  /usr/bin/as -a64 -mppc64 -mlittle-endian -mpower8 \
   -I ./arch/powerpc/include -I ./arch/powerpc/include/generated \
   -I ./include -I ./arch/powerpc/include/uapi \
   -I ./arch/powerpc/include/generated/uapi -I ./include/uapi \
   -I ./include/generated/uapi -I arch/powerpc -I arch/powerpc \
   -maltivec -mpower4 -o init/do_mounts.o /tmp/do_mounts-3b0a3d.s
  /tmp/do_mounts-51ce54.s:748: Error: unrecognized opcode: `isel'

GCC does include -many, so the GCC driven gas call will succeed:

  as -v -I ./arch/powerpc/include -I ./arch/powerpc/include/generated -I
  ./include -I ./arch/powerpc/include/uapi
  -I ./arch/powerpc/include/generated/uapi -I ./include/uapi
  -I ./include/generated/uapi -I arch/powerpc -I arch/powerpc
   -a64 -mpower8 -many -mlittle -maltivec -mpower4 -o init/do_mounts.o

Note that isel is power7 and above for IBM CPUs. GCC only generates it
for Power9 and above, but the above test was run against the clang
generated assembly.

Peter Bergner explains:

  When using -many -mpower4, gas will first try and find a matching
  power4 mnemonic and failing that, it will then allow any valid
  mnemonic that gas knows about. GCC's use of -many predates me
  though.

  IIRC, Alan looked at trying to remove it, but I forget why he
  didn't. Could be either a gcc or gas issue at the time. I'm not sure
  whether issue still exists or not. He and I have modified how gas
  works internally a fair amount since he tried removing gcc use of
  -many.

  I will also note that when using -many, gas will choose the first
  mnemonic that matches in the mnemonic table and we have (mostly)
  sorted the table so that server mnemonics show up earlier in the
  table than other mnemonics, so they'll be seen/chosen first.

By explicitly setting -many we can build with Clang and GCC while
retaining the -mpower4 option.

Signed-off-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
 		2018-10-13 22:21:25 +11:00
Documentation powerpc: Wire up memtest 2018-10-03 16:12:47 +10:00
LICENSES LICENSES: Add Linux-OpenIB license text 2018-04-27 16:41:53 -06:00
arch powerpc/Makefile: Fix PPC_BOOK3S_64 ASFLAGS 2018-10-13 22:21:25 +11:00
block block: bfq: swap puts in bfqg_and_blkg_put 2018-09-06 11:32:58 -06:00
certs export.h: remove VMLINUX_SYMBOL() and VMLINUX_SYMBOL_STR() 2018-08-22 23:21:44 +09:00
crypto DMAengine updates for v4.19-rc1 2018-08-18 15:55:59 -07:00
drivers powerpc/eeh: Cleanup eeh_pe_state_mark() 2018-10-13 22:21:25 +11:00
firmware
…
fs afs: Fix cell specification to permit an empty address list 2018-09-07 16:39:44 -07:00
include macintosh: Use common code to access RTC 2018-10-08 22:53:10 +11:00
init Kbuild updates for v4.19 (2nd) 2018-08-25 13:40:38 -07:00
ipc ipc/shm: properly return EIDRM in shm_lock() 2018-09-04 16:45:02 -07:00
kernel Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-09-09 06:55:27 -07:00
lib lib/xz: Put CRC32_POLY_LE in xz_private.h 2018-10-02 08:44:59 +10:00
mm for-linus-20180906 2018-09-06 14:01:15 -07:00
net Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-09-04 12:45:11 -07:00
samples samples/bpf: all XDP samples should unload xdp/bpf prog on SIGTERM 2018-08-16 21:55:32 +02:00
scripts Kbuild fixes for v4.19 2018-09-09 05:42:11 -07:00
security - Fix for bad debug check when converting secids to secctx 2018-09-06 09:42:14 -07:00
sound ALSA: hda: Fix several mismatch for register mask and value 2018-09-03 23:47:40 +02:00
tools Merge branch 'fixes' into next 2018-10-09 16:51:05 +11:00
usr initramfs: move gen_initramfs_list.sh from scripts/ to usr/ 2018-08-22 23:21:44 +09:00
virt KVM: Remove obsolete kvm_unmap_hva notifier backend 2018-09-07 15:06:02 +02:00
.clang-format clang-format: Set IndentWrappedFunctionNames false 2018-08-01 18:38:51 +02:00
.cocciconfig
…
.get_maintainer.ignore
…
.gitattributes
…
.gitignore
…
.mailmap libnvdimm-for-4.19_misc 2018-08-25 18:13:10 -07:00
COPYING
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CREDITS 9p: remove Ron Minnich from MAINTAINERS 2018-08-17 16:20:26 -07:00
Kbuild
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Kconfig kconfig: move the "Executable file formats" menu to fs/Kconfig.binfmt 2018-08-02 08:06:55 +09:00
MAINTAINERS i2c: xiic: Record xilinx i2c with Zynq fragment 2018-09-07 13:04:45 +02:00
Makefile Linux 4.19-rc3 2018-09-09 17:26:43 -07:00
README
…

README 

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
See Documentation/00-INDEX for a list of what is contained in each file.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.