powerpc: xor_vmx: Add '-mhard-float' to CFLAGS

[ Upstream commit 35f20786c481d5ced9283ff42de5c69b65e5ed13 ]

arch/powerpc/lib/xor_vmx.o is built with '-msoft-float' (from the main
powerpc Makefile)

powerpc: xor_vmx: Add '-mhard-float' to CFLAGS

[ Upstream commit 35f20786c481d5ced9283ff42de5c69b65e5ed13 ]

arch/powerpc/lib/xor_vmx.o is built with '-msoft-float' (from the main
powerpc Makefile) and '-maltivec' (from its CFLAGS), which causes an
error when building with clang after a recent change in main:

error: option '-msoft-float' cannot be specified with '-maltivec'
make[6]: *** [scripts/Makefile.build:243: arch/powerpc/lib/xor_vmx.o] Error 1

Explicitly add '-mhard-float' before '-maltivec' in xor_vmx.o's CFLAGS
to override the previous inclusion of '-msoft-float' (as the last option
wins), which matches how other areas of the kernel use '-maltivec', such
as AMDGPU.

Cc: stable@vger.kernel.org
Closes: https://github.com/ClangBuiltLinux/linux/issues/1986
Link: https://github.com/llvm/llvm-project/commit/4792f912b232141ecba4cbae538873be3c28556c
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240127-ppc-xor_vmx-drop-msoft-float-v1-1-f24140e81376@kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>

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powerpc: xor_vmx: Add '-mhard-float' to CFLAGS

[ Upstream commit 35f20786c481d5ced9283ff42de5c69b65e5ed13 ]

arch/powerpc/lib/xor_vmx.o is built with '-msoft-float' (from the main
powerpc Makefile)

powerpc: xor_vmx: Add '-mhard-float' to CFLAGS

[ Upstream commit 35f20786c481d5ced9283ff42de5c69b65e5ed13 ]

arch/powerpc/lib/xor_vmx.o is built with '-msoft-float' (from the main
powerpc Makefile) and '-maltivec' (from its CFLAGS), which causes an
error when building with clang after a recent change in main:

error: option '-msoft-float' cannot be specified with '-maltivec'
make[6]: *** [scripts/Makefile.build:243: arch/powerpc/lib/xor_vmx.o] Error 1

Explicitly add '-mhard-float' before '-maltivec' in xor_vmx.o's CFLAGS
to override the previous inclusion of '-msoft-float' (as the last option
wins), which matches how other areas of the kernel use '-maltivec', such
as AMDGPU.

Cc: stable@vger.kernel.org
Closes: https://github.com/ClangBuiltLinux/linux/issues/1986
Link: https://github.com/llvm/llvm-project/commit/4792f912b232141ecba4cbae538873be3c28556c
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240127-ppc-xor_vmx-drop-msoft-float-v1-1-f24140e81376@kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>

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powerpc: add crtsavres.o to always-y instead of extra-y

[ Upstream commit 1b1e38002648819c04773647d5242990e2824264 ]

crtsavres.o is linked to modules. However, as explained in commit
d0e628cd817f (

powerpc: add crtsavres.o to always-y instead of extra-y

[ Upstream commit 1b1e38002648819c04773647d5242990e2824264 ]

crtsavres.o is linked to modules. However, as explained in commit
d0e628cd817f ("kbuild: doc: clarify the difference between extra-y
and always-y"), 'make modules' does not build extra-y.

For example, the following command fails:

$ make ARCH=powerpc LLVM=1 KBUILD_MODPOST_WARN=1 mrproper ps3_defconfig modules
[snip]
LD [M] arch/powerpc/platforms/cell/spufs/spufs.ko
ld.lld: error: cannot open arch/powerpc/lib/crtsavres.o: No such file or directory
make[3]: *** [scripts/Makefile.modfinal:56: arch/powerpc/platforms/cell/spufs/spufs.ko] Error 1
make[2]: *** [Makefile:1844: modules] Error 2
make[1]: *** [/home/masahiro/workspace/linux-kbuild/Makefile:350: __build_one_by_one] Error 2
make: *** [Makefile:234: __sub-make] Error 2

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Fixes: baa25b571a16 ("powerpc/64: Do not link crtsavres.o in vmlinux")
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20231120232332.4100288-1-masahiroy@kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>

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powerpc: Drop zalloc_maybe_bootmem()

The only callers of zalloc_maybe_bootmem() are PCI setup routines. These
used to be called early during boot before slab setup, and also during
runtime due to ho

powerpc: Drop zalloc_maybe_bootmem()

The only callers of zalloc_maybe_bootmem() are PCI setup routines. These
used to be called early during boot before slab setup, and also during
runtime due to hotplug.

But commit 5537fcb319d0 ("powerpc/pci: Add ppc_md.discover_phbs()")
moved the boot-time calls later, after slab setup, meaning there's no
longer any need for zalloc_maybe_bootmem(), kzalloc() can be used in all
cases.

Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230823055430.752550-1-mpe@ellerman.id.au

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powerpc: remove checks for binutils older than 2.25

Commit e4412739472b ("Documentation: raise minimum supported version of
binutils to 2.25") allows us to remove the checks for old binutils.

There

powerpc: remove checks for binutils older than 2.25

Commit e4412739472b ("Documentation: raise minimum supported version of
binutils to 2.25") allows us to remove the checks for old binutils.

There is no more user for ld-ifversion. Remove it as well.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230119082250.151485-1-masahiroy@kernel.org

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powerpc/kcsan: Add exclusions from instrumentation

Exclude various incompatible compilation units from KCSAN
instrumentation.

Signed-off-by: Rohan McLure <rmclure@linux.ibm.com>
Signed-off-by: Mich

powerpc/kcsan: Add exclusions from instrumentation

Exclude various incompatible compilation units from KCSAN
instrumentation.

Signed-off-by: Rohan McLure <rmclure@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20230206021801.105268-2-rmclure@linux.ibm.com

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powerpc/qspinlock: powerpc qspinlock implementation

Add a powerpc specific implementation of queued spinlocks. This is the
build framework with a very simple (non-queued) spinlock implementation
to

powerpc/qspinlock: powerpc qspinlock implementation

Add a powerpc specific implementation of queued spinlocks. This is the
build framework with a very simple (non-queued) spinlock implementation
to begin with. Later changes add queueing, and other features and
optimisations one-at-a-time. It is done this way to more easily see how
the queued spinlocks are built, and to make performance and correctness
bisects more useful.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Drop paravirt.h & processor.h changes to fix 32-bit build]
[mpe: Fix 32-bit build of qspinlock.o & disallow GENERIC_LOCKBREAK per Nick]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/CONLLQB6DCJU.2ZPOS7T6S5GRR@bobo

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powerpc/kasan: Don't instrument non-maskable or raw interrupts

Disable address sanitization for raw and non-maskable interrupt
handlers, because they can run in real mode, where we cannot access
the

powerpc/kasan: Don't instrument non-maskable or raw interrupts

Disable address sanitization for raw and non-maskable interrupt
handlers, because they can run in real mode, where we cannot access
the shadow memory. (Note that kasan_arch_is_ready() doesn't test for
real mode, since it is a static branch for speed, and in any case not
all the entry points to the generic KASAN code are protected by
kasan_arch_is_ready guards.)

The changes to interrupt_nmi_enter/exit_prepare() look larger than
they actually are. The changes are equivalent to adding
!IS_ENABLED(CONFIG_KASAN) to the conditions for calling nmi_enter() or
nmi_exit() in real mode. That is, the code is equivalent to using the
following condition for calling nmi_enter/exit:

if (((!IS_ENABLED(CONFIG_PPC_BOOK3S_64) ||
!firmware_has_feature(FW_FEATURE_LPAR) ||
radix_enabled()) &&
!IS_ENABLED(CONFIG_KASAN) ||
(mfmsr() & MSR_DR))

That unwieldy condition has been split into several statements with
comments, for easier reading.

The nmi_ipi_lock functions that call atomic functions (i.e.,
nmi_ipi_lock_start(), nmi_ipi_lock() and nmi_ipi_unlock()), besides
being marked noinstr, now call arch_atomic_* functions instead of
atomic_* functions because with KASAN enabled, the atomic_* functions
are wrappers which explicitly do address sanitization on their
arguments. Since we are trying to avoid address sanitization, we have
to use the lower-level arch_atomic_* versions.

In hv_nmi_check_nonrecoverable(), the regs_set_unrecoverable() call
has been open-coded so as to avoid having to either trust the inlining
or mark regs_set_unrecoverable() as noinstr.

[paulus@ozlabs.org: combined a few work-in-progress commits of
Daniel's and wrote the commit message.]

Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/YoTFGaKM8Pd46PIK@cleo

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powerpc/32: Fix boot failure with GCC latent entropy plugin

Boot fails with GCC latent entropy plugin enabled.

This is due to early boot functions trying to access 'latent_entropy'
global data whil

powerpc/32: Fix boot failure with GCC latent entropy plugin

Boot fails with GCC latent entropy plugin enabled.

This is due to early boot functions trying to access 'latent_entropy'
global data while the kernel is not relocated at its final
destination yet.

As there is no way to tell GCC to use PTRRELOC() to access it,
disable latent entropy plugin in early_32.o and feature-fixups.o and
code-patching.o

Fixes: 38addce8b600 ("gcc-plugins: Add latent_entropy plugin")
Cc: stable@vger.kernel.org # v4.9+
Reported-by: Erhard Furtner <erhard_f@mailbox.org>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=215217
Link: https://lore.kernel.org/r/2bac55483b8daf5b1caa163a45fa5f9cdbe18be4.1640178426.git.christophe.leroy@csgroup.eu

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powerpc/code-patching: Move code patching selftests in its own file

Code patching selftests are half of code-patching.c.
As they are guarded by CONFIG_CODE_PATCHING_SELFTESTS,
they'd be better in th

powerpc/code-patching: Move code patching selftests in its own file

Code patching selftests are half of code-patching.c.
As they are guarded by CONFIG_CODE_PATCHING_SELFTESTS,
they'd be better in their own file.

Also add a missing __init for instr_is_branch_to_addr()

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/c0c30504f04eb546a48ff77127a8bccd12a3d809.1638446239.git.christophe.leroy@csgroup.eu

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powerpc/code-patching: Use test_trampoline for prefixed patch test

Use the dedicated test_trampoline function for testing prefixed
patching like other tests and remove the hand coded assembly stuff.

powerpc/code-patching: Use test_trampoline for prefixed patch test

Use the dedicated test_trampoline function for testing prefixed
patching like other tests and remove the hand coded assembly stuff.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/a450ef3f8653f75e1bd9aaf7a3889d379752f33b.1638446239.git.christophe.leroy@csgroup.eu

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isystem: delete global -isystem compile option

Further isolate kernel from userspace, prevent accidental inclusion of
undesireable headers, mainly float.h and stdatomic.h.

nds32 keeps -isystem glob

isystem: delete global -isystem compile option

Further isolate kernel from userspace, prevent accidental inclusion of
undesireable headers, mainly float.h and stdatomic.h.

nds32 keeps -isystem globally due to intrinsics used in entrenched header.

-isystem is selectively reenabled for some files, again, for intrinsics.

Compile tested on:

hexagon-defconfig hexagon-allmodconfig
alpha-allmodconfig alpha-allnoconfig alpha-defconfig arm64-allmodconfig
arm64-allnoconfig arm64-defconfig arm-am200epdkit arm-aspeed_g4
arm-aspeed_g5 arm-assabet arm-at91_dt arm-axm55xx arm-badge4 arm-bcm2835
arm-cerfcube arm-clps711x arm-cm_x300 arm-cns3420vb arm-colibri_pxa270
arm-colibri_pxa300 arm-collie arm-corgi arm-davinci_all arm-dove
arm-ep93xx arm-eseries_pxa arm-exynos arm-ezx arm-footbridge arm-gemini
arm-h3600 arm-h5000 arm-hackkit arm-hisi arm-imote2 arm-imx_v4_v5
arm-imx_v6_v7 arm-integrator arm-iop32x arm-ixp4xx arm-jornada720
arm-keystone arm-lart arm-lpc18xx arm-lpc32xx arm-lpd270 arm-lubbock
arm-magician arm-mainstone arm-milbeaut_m10v arm-mini2440 arm-mmp2
arm-moxart arm-mps2 arm-multi_v4t arm-multi_v5 arm-multi_v7 arm-mv78xx0
arm-mvebu_v5 arm-mvebu_v7 arm-mxs arm-neponset arm-netwinder arm-nhk8815
arm-omap1 arm-omap2plus arm-orion5x arm-oxnas_v6 arm-palmz72 arm-pcm027
arm-pleb arm-pxa arm-pxa168 arm-pxa255-idp arm-pxa3xx arm-pxa910
arm-qcom arm-realview arm-rpc arm-s3c2410 arm-s3c6400 arm-s5pv210
arm-sama5 arm-shannon arm-shmobile arm-simpad arm-socfpga arm-spear13xx
arm-spear3xx arm-spear6xx arm-spitz arm-stm32 arm-sunxi arm-tct_hammer
arm-tegra arm-trizeps4 arm-u8500 arm-versatile arm-vexpress arm-vf610m4
arm-viper arm-vt8500_v6_v7 arm-xcep arm-zeus csky-allmodconfig
csky-allnoconfig csky-defconfig h8300-edosk2674 h8300-h8300h-sim
h8300-h8s-sim i386-allmodconfig i386-allnoconfig i386-defconfig
ia64-allmodconfig ia64-allnoconfig ia64-bigsur ia64-generic ia64-gensparse
ia64-tiger ia64-zx1 m68k-amcore m68k-amiga m68k-apollo m68k-atari
m68k-bvme6000 m68k-hp300 m68k-m5208evb m68k-m5249evb m68k-m5272c3
m68k-m5275evb m68k-m5307c3 m68k-m5407c3 m68k-m5475evb m68k-mac
m68k-multi m68k-mvme147 m68k-mvme16x m68k-q40 m68k-stmark2 m68k-sun3
m68k-sun3x microblaze-allmodconfig microblaze-allnoconfig microblaze-mmu
mips-ar7 mips-ath25 mips-ath79 mips-bcm47xx mips-bcm63xx mips-bigsur
mips-bmips_be mips-bmips_stb mips-capcella mips-cavium_octeon mips-ci20
mips-cobalt mips-cu1000-neo mips-cu1830-neo mips-db1xxx mips-decstation
mips-decstation_64 mips-decstation_r4k mips-e55 mips-fuloong2e
mips-gcw0 mips-generic mips-gpr mips-ip22 mips-ip27 mips-ip28 mips-ip32
mips-jazz mips-jmr3927 mips-lemote2f mips-loongson1b mips-loongson1c
mips-loongson2k mips-loongson3 mips-malta mips-maltaaprp mips-malta_kvm
mips-malta_qemu_32r6 mips-maltasmvp mips-maltasmvp_eva mips-maltaup
mips-maltaup_xpa mips-mpc30x mips-mtx1 mips-nlm_xlp mips-nlm_xlr
mips-omega2p mips-pic32mzda mips-pistachio mips-qi_lb60 mips-rb532
mips-rbtx49xx mips-rm200 mips-rs90 mips-rt305x mips-sb1250_swarm
mips-tb0219 mips-tb0226 mips-tb0287 mips-vocore2 mips-workpad mips-xway
nds32-allmodconfig nds32-allnoconfig nds32-defconfig nios2-10m50
nios2-3c120 nios2-allmodconfig nios2-allnoconfig openrisc-allmodconfig
openrisc-allnoconfig openrisc-or1klitex openrisc-or1ksim
openrisc-simple_smp parisc-allnoconfig parisc-generic-32bit
parisc-generic-64bit powerpc-acadia powerpc-adder875 powerpc-akebono
powerpc-amigaone powerpc-arches powerpc-asp8347 powerpc-bamboo
powerpc-bluestone powerpc-canyonlands powerpc-cell powerpc-chrp32
powerpc-cm5200 powerpc-currituck powerpc-ebony powerpc-eiger
powerpc-ep8248e powerpc-ep88xc powerpc-fsp2 powerpc-g5 powerpc-gamecube
powerpc-ge_imp3a powerpc-holly powerpc-icon powerpc-iss476-smp
powerpc-katmai powerpc-kilauea powerpc-klondike powerpc-kmeter1
powerpc-ksi8560 powerpc-linkstation powerpc-lite5200b powerpc-makalu
powerpc-maple powerpc-mgcoge powerpc-microwatt powerpc-motionpro
powerpc-mpc512x powerpc-mpc5200 powerpc-mpc7448_hpc2 powerpc-mpc8272_ads
powerpc-mpc8313_rdb powerpc-mpc8315_rdb powerpc-mpc832x_mds
powerpc-mpc832x_rdb powerpc-mpc834x_itx powerpc-mpc834x_itxgp
powerpc-mpc834x_mds powerpc-mpc836x_mds powerpc-mpc836x_rdk
powerpc-mpc837x_mds powerpc-mpc837x_rdb powerpc-mpc83xx
powerpc-mpc8540_ads powerpc-mpc8560_ads powerpc-mpc85xx_cds
powerpc-mpc866_ads powerpc-mpc885_ads powerpc-mvme5100 powerpc-obs600
powerpc-pasemi powerpc-pcm030 powerpc-pmac32 powerpc-powernv
powerpc-ppa8548 powerpc-ppc40x powerpc-ppc44x powerpc-ppc64
powerpc-ppc64e powerpc-ppc6xx powerpc-pq2fads powerpc-ps3
powerpc-pseries powerpc-rainier powerpc-redwood powerpc-sam440ep
powerpc-sbc8548 powerpc-sequoia powerpc-skiroot powerpc-socrates
powerpc-storcenter powerpc-stx_gp3 powerpc-taishan powerpc-tqm5200
powerpc-tqm8540 powerpc-tqm8541 powerpc-tqm8548 powerpc-tqm8555
powerpc-tqm8560 powerpc-tqm8xx powerpc-walnut powerpc-warp powerpc-wii
powerpc-xes_mpc85xx riscv-allmodconfig riscv-allnoconfig riscv-nommu_k210
riscv-nommu_k210_sdcard riscv-nommu_virt riscv-rv32 s390-allmodconfig
s390-allnoconfig s390-debug s390-zfcpdump sh-ap325rxa sh-apsh4a3a
sh-apsh4ad0a sh-dreamcast sh-ecovec24 sh-ecovec24-romimage sh-edosk7705
sh-edosk7760 sh-espt sh-hp6xx sh-j2 sh-kfr2r09 sh-kfr2r09-romimage
sh-landisk sh-lboxre2 sh-magicpanelr2 sh-microdev sh-migor sh-polaris
sh-r7780mp sh-r7785rp sh-rsk7201 sh-rsk7203 sh-rsk7264 sh-rsk7269
sh-rts7751r2d1 sh-rts7751r2dplus sh-sdk7780 sh-sdk7786 sh-se7206 sh-se7343
sh-se7619 sh-se7705 sh-se7712 sh-se7721 sh-se7722 sh-se7724 sh-se7750
sh-se7751 sh-se7780 sh-secureedge5410 sh-sh03 sh-sh2007 sh-sh7710voipgw
sh-sh7724_generic sh-sh7757lcr sh-sh7763rdp sh-sh7770_generic sh-sh7785lcr
sh-sh7785lcr_32bit sh-shmin sh-shx3 sh-titan sh-ul2 sh-urquell
sparc-allmodconfig sparc-allnoconfig sparc-sparc32 sparc-sparc64
um-i386-allmodconfig um-i386-allnoconfig um-i386-defconfig
um-x86_64-allmodconfig um-x86_64-allnoconfig x86_64-allmodconfig
x86_64-allnoconfig x86_64-defconfig xtensa-allmodconfig xtensa-allnoconfig
xtensa-audio_kc705 xtensa-cadence_csp xtensa-common xtensa-generic_kc705
xtensa-iss xtensa-nommu_kc705 xtensa-smp_lx200 xtensa-virt
xtensa-xip_kc705

Tested-by: Nathan Chancellor <nathan@kernel.org> # build (hexagon)
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

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powerpc/32: Fix boot failure with GCC latent entropy plugin

commit bba496656a73fc1d1330b49c7f82843836e9feb1 upstream.

Boot fails with GCC latent entropy plugin enabled.

This is due to early boot f

powerpc/32: Fix boot failure with GCC latent entropy plugin

commit bba496656a73fc1d1330b49c7f82843836e9feb1 upstream.

Boot fails with GCC latent entropy plugin enabled.

This is due to early boot functions trying to access 'latent_entropy'
global data while the kernel is not relocated at its final
destination yet.

As there is no way to tell GCC to use PTRRELOC() to access it,
disable latent entropy plugin in early_32.o and feature-fixups.o and
code-patching.o

Fixes: 38addce8b600 ("gcc-plugins: Add latent_entropy plugin")
Cc: stable@vger.kernel.org # v4.9+
Reported-by: Erhard Furtner <erhard_f@mailbox.org>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=215217
Link: https://lore.kernel.org/r/2bac55483b8daf5b1caa163a45fa5f9cdbe18be4.1640178426.git.christophe.leroy@csgroup.eu
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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powerpc: Only build restart_table.c for 64s

Commit 9b69d48c7516 ("powerpc/64e: remove implicit soft-masking and
interrupt exit restart logic") limited the implicit soft masking and
restart logic to

powerpc: Only build restart_table.c for 64s

Commit 9b69d48c7516 ("powerpc/64e: remove implicit soft-masking and
interrupt exit restart logic") limited the implicit soft masking and
restart logic to 64-bit Book3S only. However we are still building
restart_table.c for all 64-bit, ie. Book3E also.

There's no need to build it for 64e, and it also causes missing
prototype warnings for 64e builds, because the prototype is already
behind an #ifdef PPC_BOOK3S_64.

Fixes: 9b69d48c7516 ("powerpc/64e: remove implicit soft-masking and interrupt exit restart logic")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210701125026.292224-1-mpe@ellerman.id.au

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powerpc/64: allow alternate return locations for soft-masked interrupts

The exception table fixup adjusts a failed page fault's interrupt return
location if it was taken at an address specified in t

powerpc/64: allow alternate return locations for soft-masked interrupts

The exception table fixup adjusts a failed page fault's interrupt return
location if it was taken at an address specified in the exception table,
to a corresponding fixup handler address.

Introduce a variation of that idea which adds a fixup table for NMIs and
soft-masked asynchronous interrupts. This will be used to protect
certain critical sections that are sensitive to being clobbered by
interrupts coming in (due to using the same SPRs and/or irq soft-mask
state).

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210617155116.2167984-10-npiggin@gmail.com

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powerpc/32: Fix boot failure with CONFIG_STACKPROTECTOR

Commit 7c95d8893fb5 ("powerpc: Change calling convention for
create_branch() et. al.") complexified the frame of function
do_feature_fixups(),

powerpc/32: Fix boot failure with CONFIG_STACKPROTECTOR

Commit 7c95d8893fb5 ("powerpc: Change calling convention for
create_branch() et. al.") complexified the frame of function
do_feature_fixups(), leading to GCC setting up a stack
guard when CONFIG_STACKPROTECTOR is selected.

The problem is that do_feature_fixups() is called very early
while 'current' in r2 is not set up yet and the code is still
not at the final address used at link time.

So, like other instrumentation, stack protection needs to be
deactivated for feature-fixups.c and code-patching.c

Fixes: 7c95d8893fb5 ("powerpc: Change calling convention for create_branch() et. al.")
Cc: stable@vger.kernel.org # v5.8+
Reported-by: Jonathan Neuschaefer <j.neuschaefer@gmx.net>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Tested-by: Jonathan Neuschaefer <j.neuschaefer@gmx.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/b688fe82927b330349d9e44553363fa451ea4d95.1619715114.git.christophe.leroy@csgroup.eu

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powerpc: Move copy_inst_from_kernel_nofault()

When probe_kernel_read_inst() was created, there was no good place to
put it, so a file called lib/inst.c was dedicated for it.

Since then, probe_kerne

powerpc: Move copy_inst_from_kernel_nofault()

When probe_kernel_read_inst() was created, there was no good place to
put it, so a file called lib/inst.c was dedicated for it.

Since then, probe_kernel_read_inst() has been renamed
copy_inst_from_kernel_nofault(). And mm/maccess.h didn't exist at that
time. Today, mm/maccess.h is related to copy_from_kernel_nofault().

Move copy_inst_from_kernel_nofault() into mm/maccess.c

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/9655d8957313906b77b8db5700a0e33ce06f45e5.1618405715.git.christophe.leroy@csgroup.eu

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kbuild: LD_VERSION redenomination

Commit ccbef1674a15 ("Kbuild, lto: add ld-version and ld-ifversion
macros") introduced scripts/ld-version.sh for GCC LTO.

At that time, this script handled 5 versi

kbuild: LD_VERSION redenomination

Commit ccbef1674a15 ("Kbuild, lto: add ld-version and ld-ifversion
macros") introduced scripts/ld-version.sh for GCC LTO.

At that time, this script handled 5 version fields because GCC LTO
needed the downstream binutils. (https://lkml.org/lkml/2014/4/8/272)

The code snippet from the submitted patch was as follows:

# We need HJ Lu's Linux binutils because mainline binutils does not
# support mixing assembler and LTO code in the same ld -r object.
# XXX check if the gcc plugin ld is the expected one too
# XXX some Fedora binutils should also support it. How to check for that?
ifeq ($(call ld-ifversion,-ge,22710001,y),y)
...

However, GCC LTO was not merged into the mainline after all.
(https://lkml.org/lkml/2014/4/8/272)

So, the 4th and 5th fields were never used, and finally removed by
commit 0d61ed17dd30 ("ld-version: Drop the 4th and 5th version
components").

Since then, the last 4-digits returned by this script is always zeros.

Remove the meaningless last 4-digits. This makes the version format
consistent with GCC_VERSION, CLANG_VERSION, LLD_VERSION.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Will Deacon <will@kernel.org>
Acked-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

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powerpc/32: Fix boot failure with CONFIG_STACKPROTECTOR

commit f5668260b872e89b8d3942a8b7d4278aa9c2c981 upstream.

Commit 7c95d8893fb5 ("powerpc: Change calling convention for
create_branch() et. al

powerpc/32: Fix boot failure with CONFIG_STACKPROTECTOR

commit f5668260b872e89b8d3942a8b7d4278aa9c2c981 upstream.

Commit 7c95d8893fb5 ("powerpc: Change calling convention for
create_branch() et. al.") complexified the frame of function
do_feature_fixups(), leading to GCC setting up a stack
guard when CONFIG_STACKPROTECTOR is selected.

The problem is that do_feature_fixups() is called very early
while 'current' in r2 is not set up yet and the code is still
not at the final address used at link time.

So, like other instrumentation, stack protection needs to be
deactivated for feature-fixups.c and code-patching.c

Fixes: 7c95d8893fb5 ("powerpc: Change calling convention for create_branch() et. al.")
Cc: stable@vger.kernel.org # v5.8+
Reported-by: Jonathan Neuschaefer <j.neuschaefer@gmx.net>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Tested-by: Jonathan Neuschaefer <j.neuschaefer@gmx.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/b688fe82927b330349d9e44553363fa451ea4d95.1619715114.git.christophe.leroy@csgroup.eu
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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x86, powerpc: Rename memcpy_mcsafe() to copy_mc_to_{user, kernel}()

In reaction to a proposal to introduce a memcpy_mcsafe_fast()
implementation Linus points out that memcpy_mcsafe() is poorly named

x86, powerpc: Rename memcpy_mcsafe() to copy_mc_to_{user, kernel}()

In reaction to a proposal to introduce a memcpy_mcsafe_fast()
implementation Linus points out that memcpy_mcsafe() is poorly named
relative to communicating the scope of the interface. Specifically what
addresses are valid to pass as source, destination, and what faults /
exceptions are handled.

Of particular concern is that even though x86 might be able to handle
the semantics of copy_mc_to_user() with its common copy_user_generic()
implementation other archs likely need / want an explicit path for this
case:

On Fri, May 1, 2020 at 11:28 AM Linus Torvalds <torvalds@linux-foundation.org> wrote:
>
> On Thu, Apr 30, 2020 at 6:21 PM Dan Williams <dan.j.williams@intel.com> wrote:
> >
> > However now I see that copy_user_generic() works for the wrong reason.
> > It works because the exception on the source address due to poison
> > looks no different than a write fault on the user address to the
> > caller, it's still just a short copy. So it makes copy_to_user() work
> > for the wrong reason relative to the name.
>
> Right.
>
> And it won't work that way on other architectures. On x86, we have a
> generic function that can take faults on either side, and we use it
> for both cases (and for the "in_user" case too), but that's an
> artifact of the architecture oddity.
>
> In fact, it's probably wrong even on x86 - because it can hide bugs -
> but writing those things is painful enough that everybody prefers
> having just one function.

Replace a single top-level memcpy_mcsafe() with either
copy_mc_to_user(), or copy_mc_to_kernel().

Introduce an x86 copy_mc_fragile() name as the rename for the
low-level x86 implementation formerly named memcpy_mcsafe(). It is used
as the slow / careful backend that is supplanted by a fast
copy_mc_generic() in a follow-on patch.

One side-effect of this reorganization is that separating copy_mc_64.S
to its own file means that perf no longer needs to track dependencies
for its memcpy_64.S benchmarks.

[ bp: Massage a bit. ]

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Cc: <stable@vger.kernel.org>
Link: http://lore.kernel.org/r/CAHk-=wjSqtXAqfUJxFtWNwmguFASTgB0dz1dT3V-78Quiezqbg@mail.gmail.com
Link: https://lkml.kernel.org/r/160195561680.2163339.11574962055305783722.stgit@dwillia2-desk3.amr.corp.intel.com

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powerpc/64s: Implement queued spinlocks and rwlocks

These have shown significantly improved performance and fairness when
spinlock contention is moderate to high on very large systems.

With this se

powerpc/64s: Implement queued spinlocks and rwlocks

These have shown significantly improved performance and fairness when
spinlock contention is moderate to high on very large systems.

With this series including subsequent patches, on a 16 socket 1536
thread POWER9, a stress test such as same-file open/close from all
CPUs gets big speedups, 11620op/s aggregate with simple spinlocks vs
384158op/s (33x faster), where the difference in throughput between
the fastest and slowest thread goes from 7x to 1.4x.

Thanks to the fast path being identical in terms of atomics and
barriers (after a subsequent optimisation patch), single threaded
performance is not changed (no measurable difference).

On smaller systems, performance and fairness seems to be generally
improved. Using dbench on tmpfs as a test (that starts to run into
kernel spinlock contention), a 2-socket OpenPOWER POWER9 system was
tested with bare metal and KVM guest configurations. Results can be
found here:

https://github.com/linuxppc/issues/issues/305#issuecomment-663487453

Observations are:

- Queued spinlocks are equal when contention is insignificant, as
expected and as measured with microbenchmarks.

- When there is contention, on bare metal queued spinlocks have better
throughput and max latency at all points.

- When virtualised, queued spinlocks are slightly worse approaching
peak throughput, but significantly better throughput and max latency
at all points beyond peak, until queued spinlock maximum latency
rises when clients are 2x vCPUs.

The regressions haven't been analysed very well yet, there are a lot
of things that can be tuned, particularly the paravirtualised locking,
but the numbers already look like a good net win even on relatively
small systems.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Waiman Long <longman@redhat.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200724131423.1362108-4-npiggin@gmail.com

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powerpc: Test prefixed code patching

Expand the code-patching self-tests to includes tests for patching
prefixed instructions.

Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
[mpe: Use CONFIG_PPC

powerpc: Test prefixed code patching

Expand the code-patching self-tests to includes tests for patching
prefixed instructions.

Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
[mpe: Use CONFIG_PPC64 not __powerpc64__]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200506034050.24806-25-jniethe5@gmail.com

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powerpc: Add a probe_user_read_inst() function

Introduce a probe_user_read_inst() function to use in cases where
probe_user_read() is used for getting an instruction. This will be
more useful for pr

powerpc: Add a probe_user_read_inst() function

Introduce a probe_user_read_inst() function to use in cases where
probe_user_read() is used for getting an instruction. This will be
more useful for prefixed instructions.

Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
Reviewed-by: Alistair Popple <alistair@popple.id.au>
[mpe: Don't write to *inst on error, fold in __user annotations]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200506034050.24806-14-jniethe5@gmail.com

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powerpc/memcpy: Add memcpy_mcsafe for pmem

The pmem infrastructure uses memcpy_mcsafe in the pmem layer so as to
convert machine check exceptions into a return value on failure in case
a machine che

powerpc/memcpy: Add memcpy_mcsafe for pmem

The pmem infrastructure uses memcpy_mcsafe in the pmem layer so as to
convert machine check exceptions into a return value on failure in case
a machine check exception is encountered during the memcpy. The return
value is the number of bytes remaining to be copied.

This patch largely borrows from the copyuser_power7 logic and does not add
the VMX optimizations, largely to keep the patch simple. If needed those
optimizations can be folded in.

Signed-off-by: Balbir Singh <bsingharora@gmail.com>
[arbab@linux.ibm.com: Added symbol export]
Co-developed-by: Santosh Sivaraj <santosh@fossix.org>
Signed-off-by: Santosh Sivaraj <santosh@fossix.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190820081352.8641-7-santosh@fossix.org

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powerpc/32: activate ARCH_HAS_PMEM_API and ARCH_HAS_UACCESS_FLUSHCACHE

PPC32 also have flush_dcache_range() so it can also support
ARCH_HAS_PMEM_API and ARCH_HAS_UACCESS_FLUSHCACHE without changes.

powerpc/32: activate ARCH_HAS_PMEM_API and ARCH_HAS_UACCESS_FLUSHCACHE

PPC32 also have flush_dcache_range() so it can also support
ARCH_HAS_PMEM_API and ARCH_HAS_UACCESS_FLUSHCACHE without changes.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/a682a2f9db308c5cfe77e45aa3352e41bc9f4e33.1564554634.git.christophe.leroy@c-s.fr

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