* Re: [PATCH v2] powerpc: Allow flush_(inval_)dcache_range to work across ranges >4GB
From: Christophe Leroy @ 2019-08-26 20:08 UTC (permalink / raw)
To: Greg Kroah-Hartman, Alastair D'Silva
Cc: linux-kernel, stable, Paul Mackerras, alastair, Thomas Gleixner,
linuxppc-dev, Allison Randal
In-Reply-To: <20190826165021.GB9305@kroah.com>
Le 26/08/2019 à 18:50, Greg Kroah-Hartman a écrit :
> On Wed, Aug 21, 2019 at 10:19:27AM +1000, Alastair D'Silva wrote:
>> From: Alastair D'Silva <alastair@d-silva.org>
>>
>> The upstream commit:
>> 22e9c88d486a ("powerpc/64: reuse PPC32 static inline flush_dcache_range()")
>> has a similar effect, but since it is a rewrite of the assembler to C, is
>> too invasive for stable. This patch is a minimal fix to address the issue in
>> assembler.
>>
>> This patch applies cleanly to v5.2, v4.19 & v4.14.
>>
>> When calling flush_(inval_)dcache_range with a size >4GB, we were masking
>> off the upper 32 bits, so we would incorrectly flush a range smaller
>> than intended.
>>
>> This patch replaces the 32 bit shifts with 64 bit ones, so that
>> the full size is accounted for.
>>
>> Changelog:
>> v2
>> - Add related upstream commit
>>
>> Signed-off-by: Alastair D'Silva <alastair@d-silva.org>
>> ---
>> arch/powerpc/kernel/misc_64.S | 4 ++--
>> 1 file changed, 2 insertions(+), 2 deletions(-)
>>
>> diff --git a/arch/powerpc/kernel/misc_64.S b/arch/powerpc/kernel/misc_64.S
>> index 1ad4089dd110..d4d096f80f4b 100644
>> --- a/arch/powerpc/kernel/misc_64.S
>> +++ b/arch/powerpc/kernel/misc_64.S
>> @@ -130,7 +130,7 @@ _GLOBAL_TOC(flush_dcache_range)
>> subf r8,r6,r4 /* compute length */
>> add r8,r8,r5 /* ensure we get enough */
>> lwz r9,DCACHEL1LOGBLOCKSIZE(r10) /* Get log-2 of dcache block size */
>> - srw. r8,r8,r9 /* compute line count */
>> + srd. r8,r8,r9 /* compute line count */
>> beqlr /* nothing to do? */
>> mtctr r8
>> 0: dcbst 0,r6
>> @@ -148,7 +148,7 @@ _GLOBAL(flush_inval_dcache_range)
>> subf r8,r6,r4 /* compute length */
>> add r8,r8,r5 /* ensure we get enough */
>> lwz r9,DCACHEL1LOGBLOCKSIZE(r10)/* Get log-2 of dcache block size */
>> - srw. r8,r8,r9 /* compute line count */
>> + srd. r8,r8,r9 /* compute line count */
>> beqlr /* nothing to do? */
>> sync
>> isync
>
> I need an ack from the powerpc maintainer(s) before I can take this.
I think you already got an ack (on v1). See
https://patchwork.ozlabs.org/patch/1147403/#2239663
Christophe
^ permalink raw reply
* Re: [PATCH] bpf: handle 32-bit zext during constant blinding
From: Daniel Borkmann @ 2019-08-26 21:34 UTC (permalink / raw)
To: Naveen N. Rao, Alexei Starovoitov, Jiong Wang
Cc: bpf, linuxppc-dev, linux-kernel, netdev
In-Reply-To: <20190821192358.31922-1-naveen.n.rao@linux.vnet.ibm.com>
On 8/21/19 9:23 PM, Naveen N. Rao wrote:
> Since BPF constant blinding is performed after the verifier pass, the
> ALU32 instructions inserted for doubleword immediate loads don't have a
> corresponding zext instruction. This is causing a kernel oops on powerpc
> and can be reproduced by running 'test_cgroup_storage' with
> bpf_jit_harden=2.
>
> Fix this by emitting BPF_ZEXT during constant blinding if
> prog->aux->verifier_zext is set.
>
> Fixes: a4b1d3c1ddf6cb ("bpf: verifier: insert zero extension according to analysis result")
> Reported-by: Michael Ellerman <mpe@ellerman.id.au>
> Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
LGTM, applied to bpf, thanks!
^ permalink raw reply
* Re: [PATCH 03/11] asm-generic: add generic dwarf definition
From: Changbin Du @ 2019-08-26 22:25 UTC (permalink / raw)
To: Peter Zijlstra
Cc: linux-arch, linux-s390, linux-parisc, Jonathan Corbet, linux-sh,
x86, linux-doc, linux-kernel, Steven Rostedt, linux-mips,
Ingo Molnar, Jessica Yu, sparclinux, linux-kbuild,
Thomas Gleixner, linuxppc-dev, linux-riscv, linux-arm-kernel,
Changbin Du
In-Reply-To: <20190826074215.GL2369@hirez.programming.kicks-ass.net>
Hi, Peter,
On Mon, Aug 26, 2019 at 09:42:15AM +0200, Peter Zijlstra wrote:
> On Sun, Aug 25, 2019 at 09:23:22PM +0800, Changbin Du wrote:
> > Add generic DWARF constant definitions. We will use it later.
> >
> > Signed-off-by: Changbin Du <changbin.du@gmail.com>
> > ---
> > include/asm-generic/dwarf.h | 199 ++++++++++++++++++++++++++++++++++++
> > 1 file changed, 199 insertions(+)
> > create mode 100644 include/asm-generic/dwarf.h
> >
> > diff --git a/include/asm-generic/dwarf.h b/include/asm-generic/dwarf.h
> > new file mode 100644
> > index 000000000000..c705633c2a8f
> > --- /dev/null
> > +++ b/include/asm-generic/dwarf.h
> > @@ -0,0 +1,199 @@
> > +/* SPDX-License-Identifier: GPL-2.0
> > + *
> > + * Architecture independent definitions of DWARF.
> > + *
> > + * Copyright (C) 2019 Changbin Du <changbin.du@gmail.com>
>
> You're claiming copyright on dwarf definitions? ;-)
>
> I'm thinking only Oracle was daft enough to think stuff like that was
> copyrightable.
>
ok, let me remove copyright line. I think SPDX claim is okay, right?
> Also; I think it would be very good to not use/depend on DWARF for this.
>
It only includes the DWARF expersion opcodes, not all of dwarf stuffs.
> You really don't need all of DWARF; I'm thikning you only need a few
> types; for location we already have regs_get_kernel_argument() which
> has all the logic to find the n-th argument.
>
regs_get_kernel_argument() can handle most cases, but if the size of one paramater
exceeds 64bit (it is rare in kernel), we must recalculate the locations. So I think
dwarf location descriptor is the most accurate one.
--
Cheers,
Changbin Du
^ permalink raw reply
* Re: [PATCH 05/11] ftrace: create memcache for hash entries
From: Changbin Du @ 2019-08-26 22:35 UTC (permalink / raw)
To: Peter Zijlstra
Cc: linux-arch, linux-s390, linux-parisc, Jonathan Corbet, linux-sh,
x86, linux-doc, linux-kernel, Steven Rostedt, linux-mips,
Ingo Molnar, Jessica Yu, sparclinux, linux-kbuild,
Thomas Gleixner, linuxppc-dev, linux-riscv, linux-arm-kernel,
Changbin Du
In-Reply-To: <20190826074437.GM2369@hirez.programming.kicks-ass.net>
On Mon, Aug 26, 2019 at 09:44:37AM +0200, Peter Zijlstra wrote:
> On Sun, Aug 25, 2019 at 09:23:24PM +0800, Changbin Du wrote:
> > When CONFIG_FTRACE_FUNC_PROTOTYPE is enabled, thousands of
> > ftrace_func_entry instances are created. So create a dedicated
> > memcache to enhance performance.
> >
> > Signed-off-by: Changbin Du <changbin.du@gmail.com>
> > ---
> > kernel/trace/ftrace.c | 17 ++++++++++++++++-
> > 1 file changed, 16 insertions(+), 1 deletion(-)
> >
> > diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
> > index a314f0768b2c..cfcb8dad93ea 100644
> > --- a/kernel/trace/ftrace.c
> > +++ b/kernel/trace/ftrace.c
> > @@ -94,6 +94,8 @@ struct ftrace_ops *function_trace_op __read_mostly = &ftrace_list_end;
> > /* What to set function_trace_op to */
> > static struct ftrace_ops *set_function_trace_op;
> >
> > +struct kmem_cache *hash_entry_cache;
> > +
> > static bool ftrace_pids_enabled(struct ftrace_ops *ops)
> > {
> > struct trace_array *tr;
> > @@ -1169,7 +1171,7 @@ static int add_hash_entry(struct ftrace_hash *hash, unsigned long ip,
> > {
> > struct ftrace_func_entry *entry;
> >
> > - entry = kmalloc(sizeof(*entry), GFP_KERNEL);
> > + entry = kmem_cache_alloc(hash_entry_cache, GFP_KERNEL);
> > if (!entry)
> > return -ENOMEM;
> >
> > @@ -6153,6 +6155,15 @@ void __init ftrace_init(void)
> > if (ret)
> > goto failed;
> >
> > + hash_entry_cache = kmem_cache_create("ftrace-hash",
> > + sizeof(struct ftrace_func_entry),
> > + sizeof(struct ftrace_func_entry),
> > + 0, NULL);
> > + if (!hash_entry_cache) {
> > + pr_err("failed to create ftrace hash entry cache\n");
> > + goto failed;
> > + }
>
> Wait what; you already have then in the binary image, now you're
> allocating extra memory for each of them?
>
No, here we only allocate ftrace hash entries. The prototype data is not copied.
The entry->priv points to prototype data in binary.
> Did you look at what ORC does? Is the binary search really not fast
> enough?
For ftrace, binary search is not enough. Just like the hash tables
(ftrace_graph_notrace_hash, ftrace_graph_hash) we already have which is used to
filter traced functions.
--
Cheers,
Changbin Du
^ permalink raw reply
* Re: [PATCH 01/11] ftrace: move recordmcount tools to scripts/ftrace
From: Steven Rostedt @ 2019-08-26 22:44 UTC (permalink / raw)
To: Changbin Du
Cc: linux-arch, Jonathan Corbet, linux-parisc, linux-doc, linux-sh,
linux-s390, John F . Reiser, x86, linux-kernel, linux-mips,
Ingo Molnar, Jessica Yu, sparclinux, linux-kbuild,
Thomas Gleixner, linuxppc-dev, linux-riscv, linux-arm-kernel,
Matt Helsley
In-Reply-To: <20190825132330.5015-2-changbin.du@gmail.com>
On Sun, 25 Aug 2019 21:23:20 +0800
Changbin Du <changbin.du@gmail.com> wrote:
> Move ftrace tools to its own directory. We will add another tool later.
>
> Cc: John F. Reiser <jreiser@BitWagon.com>
> Signed-off-by: Changbin Du <changbin.du@gmail.com>
> ---
> scripts/.gitignore | 1 -
> scripts/Makefile | 2 +-
> scripts/Makefile.build | 10 +++++-----
> scripts/ftrace/.gitignore | 4 ++++
> scripts/ftrace/Makefile | 4 ++++
> scripts/{ => ftrace}/recordmcount.c | 0
> scripts/{ => ftrace}/recordmcount.h | 0
> scripts/{ => ftrace}/recordmcount.pl | 0
> 8 files changed, 14 insertions(+), 7 deletions(-)
> create mode 100644 scripts/ftrace/.gitignore
> create mode 100644 scripts/ftrace/Makefile
> rename scripts/{ => ftrace}/recordmcount.c (100%)
> rename scripts/{ => ftrace}/recordmcount.h (100%)
> rename scripts/{ => ftrace}/recordmcount.pl (100%)
> mode change 100755 => 100644
Note, we are in the process of merging recordmcount with objtool. It
would be better to continue from that work.
http://lkml.kernel.org/r/2767f55f4a5fbf30ba0635aed7a9c5ee92ac07dd.1563992889.git.mhelsley@vmware.com
-- Steve
>
> diff --git a/scripts/.gitignore b/scripts/.gitignore
> index 17f8cef88fa8..1b5b5d595d80 100644
> --- a/scripts/.gitignore
> +++ b/scripts/.gitignore
> @@ -6,7 +6,6 @@ conmakehash
> kallsyms
> pnmtologo
> unifdef
> -recordmcount
> sortextable
> asn1_compiler
> extract-cert
> diff --git a/scripts/Makefile b/scripts/Makefile
> index 16bcb8087899..d5992def49a8 100644
> --- a/scripts/Makefile
> +++ b/scripts/Makefile
> @@ -14,7 +14,6 @@ hostprogs-$(CONFIG_BUILD_BIN2C) += bin2c
> hostprogs-$(CONFIG_KALLSYMS) += kallsyms
> hostprogs-$(CONFIG_LOGO) += pnmtologo
> hostprogs-$(CONFIG_VT) += conmakehash
> -hostprogs-$(BUILD_C_RECORDMCOUNT) += recordmcount
> hostprogs-$(CONFIG_BUILDTIME_EXTABLE_SORT) += sortextable
> hostprogs-$(CONFIG_ASN1) += asn1_compiler
> hostprogs-$(CONFIG_MODULE_SIG) += sign-file
> @@ -34,6 +33,7 @@ hostprogs-y += unifdef
> subdir-$(CONFIG_GCC_PLUGINS) += gcc-plugins
> subdir-$(CONFIG_MODVERSIONS) += genksyms
> subdir-$(CONFIG_SECURITY_SELINUX) += selinux
> +subdir-$(CONFIG_FTRACE) += ftrace
>
> # Let clean descend into subdirs
> subdir- += basic dtc gdb kconfig mod package
> diff --git a/scripts/Makefile.build b/scripts/Makefile.build
> index 2f66ed388d1c..67558983c518 100644
> --- a/scripts/Makefile.build
> +++ b/scripts/Makefile.build
> @@ -188,18 +188,18 @@ endif
> # files, including recordmcount.
> sub_cmd_record_mcount = \
> if [ $(@) != "scripts/mod/empty.o" ]; then \
> - $(objtree)/scripts/recordmcount $(RECORDMCOUNT_FLAGS) "$(@)"; \
> + $(objtree)/scripts/ftrace/recordmcount $(RECORDMCOUNT_FLAGS) "$(@)"; \
> fi;
> -recordmcount_source := $(srctree)/scripts/recordmcount.c \
> - $(srctree)/scripts/recordmcount.h
> +recordmcount_source := $(srctree)/scripts/ftrace/recordmcount.c \
> + $(srctree)/scripts/ftrace/recordmcount.h
> else
> -sub_cmd_record_mcount = perl $(srctree)/scripts/recordmcount.pl "$(ARCH)" \
> +sub_cmd_record_mcount = perl $(srctree)/scripts/ftrace/recordmcount.pl "$(ARCH)" \
> "$(if $(CONFIG_CPU_BIG_ENDIAN),big,little)" \
> "$(if $(CONFIG_64BIT),64,32)" \
> "$(OBJDUMP)" "$(OBJCOPY)" "$(CC) $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS)" \
> "$(LD) $(KBUILD_LDFLAGS)" "$(NM)" "$(RM)" "$(MV)" \
> "$(if $(part-of-module),1,0)" "$(@)";
> -recordmcount_source := $(srctree)/scripts/recordmcount.pl
> +recordmcount_source := $(srctree)/scripts/ftrace/recordmcount.pl
> endif # BUILD_C_RECORDMCOUNT
> cmd_record_mcount = $(if $(findstring $(strip $(CC_FLAGS_FTRACE)),$(_c_flags)), \
> $(sub_cmd_record_mcount))
> diff --git a/scripts/ftrace/.gitignore b/scripts/ftrace/.gitignore
> new file mode 100644
> index 000000000000..54d582c8faad
> --- /dev/null
> +++ b/scripts/ftrace/.gitignore
> @@ -0,0 +1,4 @@
> +#
> +# Generated files
> +#
> +recordmcount
> diff --git a/scripts/ftrace/Makefile b/scripts/ftrace/Makefile
> new file mode 100644
> index 000000000000..6797e51473e5
> --- /dev/null
> +++ b/scripts/ftrace/Makefile
> @@ -0,0 +1,4 @@
> +# SPDX-License-Identifier: GPL-2.0
> +
> +hostprogs-$(BUILD_C_RECORDMCOUNT) += recordmcount
> +always := $(hostprogs-y)
> diff --git a/scripts/recordmcount.c b/scripts/ftrace/recordmcount.c
> similarity index 100%
> rename from scripts/recordmcount.c
> rename to scripts/ftrace/recordmcount.c
> diff --git a/scripts/recordmcount.h b/scripts/ftrace/recordmcount.h
> similarity index 100%
> rename from scripts/recordmcount.h
> rename to scripts/ftrace/recordmcount.h
> diff --git a/scripts/recordmcount.pl b/scripts/ftrace/recordmcount.pl
> old mode 100755
> new mode 100644
> similarity index 100%
> rename from scripts/recordmcount.pl
> rename to scripts/ftrace/recordmcount.pl
^ permalink raw reply
* Re: [PATCH] powerpc: Avoid clang warnings around setjmp and longjmp
From: Nathan Chancellor @ 2019-08-27 0:12 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Paul Mackerras, Michael Ellerman,
Nick Desaulniers
Cc: clang-built-linux, linuxppc-dev, linux-kernel, stable
In-Reply-To: <20190812023214.107817-1-natechancellor@gmail.com>
On Sun, Aug 11, 2019 at 07:32:15PM -0700, Nathan Chancellor wrote:
> Commit aea447141c7e ("powerpc: Disable -Wbuiltin-requires-header when
> setjmp is used") disabled -Wbuiltin-requires-header because of a warning
> about the setjmp and longjmp declarations.
>
> r367387 in clang added another diagnostic around this, complaining that
> there is no jmp_buf declaration.
>
> In file included from ../arch/powerpc/xmon/xmon.c:47:
> ../arch/powerpc/include/asm/setjmp.h:10:13: error: declaration of
> built-in function 'setjmp' requires the declaration of the 'jmp_buf'
> type, commonly provided in the header <setjmp.h>.
> [-Werror,-Wincomplete-setjmp-declaration]
> extern long setjmp(long *);
> ^
> ../arch/powerpc/include/asm/setjmp.h:11:13: error: declaration of
> built-in function 'longjmp' requires the declaration of the 'jmp_buf'
> type, commonly provided in the header <setjmp.h>.
> [-Werror,-Wincomplete-setjmp-declaration]
> extern void longjmp(long *, long);
> ^
> 2 errors generated.
>
> Take the same approach as the above commit by disabling the warning for
> the same reason, we provide our own longjmp/setjmp function.
>
> Cc: stable@vger.kernel.org # 4.19+
> Link: https://github.com/ClangBuiltLinux/linux/issues/625
> Link: https://github.com/llvm/llvm-project/commit/3be25e79477db2d31ac46493d97eca8c20592b07
> Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
> ---
>
> It may be worth using -fno-builtin-setjmp and -fno-builtin-longjmp
> instead as it makes it clear to clang that we are not using the builtin
> longjmp and setjmp functions, which I think is why these warnings are
> appearing (at least according to the commit that introduced this waring).
>
> Sample patch:
> https://github.com/ClangBuiltLinux/linux/issues/625#issuecomment-519251372
>
> However, this is the most conservative approach, as I have already had
> someone notice this error when building LLVM with PGO on tip of tree
> LLVM.
>
> arch/powerpc/kernel/Makefile | 5 +++--
> arch/powerpc/xmon/Makefile | 5 +++--
> 2 files changed, 6 insertions(+), 4 deletions(-)
>
> diff --git a/arch/powerpc/kernel/Makefile b/arch/powerpc/kernel/Makefile
> index ea0c69236789..44e340ed4722 100644
> --- a/arch/powerpc/kernel/Makefile
> +++ b/arch/powerpc/kernel/Makefile
> @@ -5,8 +5,9 @@
>
> CFLAGS_ptrace.o += -DUTS_MACHINE='"$(UTS_MACHINE)"'
>
> -# Disable clang warning for using setjmp without setjmp.h header
> -CFLAGS_crash.o += $(call cc-disable-warning, builtin-requires-header)
> +# Avoid clang warnings about longjmp and setjmp built-ins (inclusion of setjmp.h and declaration of jmp_buf type)
> +CFLAGS_crash.o += $(call cc-disable-warning, builtin-requires-header) \
> + $(call cc-disable-warning, incomplete-setjmp-declaration)
>
> ifdef CONFIG_PPC64
> CFLAGS_prom_init.o += $(NO_MINIMAL_TOC)
> diff --git a/arch/powerpc/xmon/Makefile b/arch/powerpc/xmon/Makefile
> index f142570ad860..53f341391210 100644
> --- a/arch/powerpc/xmon/Makefile
> +++ b/arch/powerpc/xmon/Makefile
> @@ -1,8 +1,9 @@
> # SPDX-License-Identifier: GPL-2.0
> # Makefile for xmon
>
> -# Disable clang warning for using setjmp without setjmp.h header
> -subdir-ccflags-y := $(call cc-disable-warning, builtin-requires-header)
> +# Avoid clang warnings about longjmp and setjmp built-ins (inclusion of setjmp.h and declaration of jmp_buf type)
> +subdir-ccflags-y := $(call cc-disable-warning, builtin-requires-header) \
> + $(call cc-disable-warning, incomplete-setjmp-declaration)
>
> GCOV_PROFILE := n
> KCOV_INSTRUMENT := n
> --
> 2.23.0.rc2
>
Did any of the maintainers have any comment on this patch?
Cheers,
Nathan
^ permalink raw reply
* Re: [PATCH v2] btrfs: fix allocation of bitmap pages.
From: Nikolay Borisov @ 2019-08-26 15:40 UTC (permalink / raw)
To: dsterba, Christophe Leroy, erhard_f, Chris Mason, Josef Bacik,
David Sterba, Andrew Morton, linux-mm, stable, linuxppc-dev,
linux-kernel, linux-btrfs
In-Reply-To: <20190826153757.GW2752@twin.jikos.cz>
On 26.08.19 г. 18:37 ч., David Sterba wrote:
> On Wed, Aug 21, 2019 at 03:05:55PM +0000, Christophe Leroy wrote:
>> Various notifications of type "BUG kmalloc-4096 () : Redzone
>> overwritten" have been observed recently in various parts of
>> the kernel. After some time, it has been made a relation with
>> the use of BTRFS filesystem.
>>
>> [ 22.809700] BUG kmalloc-4096 (Tainted: G W ): Redzone overwritten
>> [ 22.809971] -----------------------------------------------------------------------------
>>
>> [ 22.810286] INFO: 0xbe1a5921-0xfbfc06cd. First byte 0x0 instead of 0xcc
>> [ 22.810866] INFO: Allocated in __load_free_space_cache+0x588/0x780 [btrfs] age=22 cpu=0 pid=224
>> [ 22.811193] __slab_alloc.constprop.26+0x44/0x70
>> [ 22.811345] kmem_cache_alloc_trace+0xf0/0x2ec
>> [ 22.811588] __load_free_space_cache+0x588/0x780 [btrfs]
>> [ 22.811848] load_free_space_cache+0xf4/0x1b0 [btrfs]
>> [ 22.812090] cache_block_group+0x1d0/0x3d0 [btrfs]
>> [ 22.812321] find_free_extent+0x680/0x12a4 [btrfs]
>> [ 22.812549] btrfs_reserve_extent+0xec/0x220 [btrfs]
>> [ 22.812785] btrfs_alloc_tree_block+0x178/0x5f4 [btrfs]
>> [ 22.813032] __btrfs_cow_block+0x150/0x5d4 [btrfs]
>> [ 22.813262] btrfs_cow_block+0x194/0x298 [btrfs]
>> [ 22.813484] commit_cowonly_roots+0x44/0x294 [btrfs]
>> [ 22.813718] btrfs_commit_transaction+0x63c/0xc0c [btrfs]
>> [ 22.813973] close_ctree+0xf8/0x2a4 [btrfs]
>> [ 22.814107] generic_shutdown_super+0x80/0x110
>> [ 22.814250] kill_anon_super+0x18/0x30
>> [ 22.814437] btrfs_kill_super+0x18/0x90 [btrfs]
>> [ 22.814590] INFO: Freed in proc_cgroup_show+0xc0/0x248 age=41 cpu=0 pid=83
>> [ 22.814841] proc_cgroup_show+0xc0/0x248
>> [ 22.814967] proc_single_show+0x54/0x98
>> [ 22.815086] seq_read+0x278/0x45c
>> [ 22.815190] __vfs_read+0x28/0x17c
>> [ 22.815289] vfs_read+0xa8/0x14c
>> [ 22.815381] ksys_read+0x50/0x94
>> [ 22.815475] ret_from_syscall+0x0/0x38
>>
>> Commit 69d2480456d1 ("btrfs: use copy_page for copying pages instead
>> of memcpy") changed the way bitmap blocks are copied. But allthough
>> bitmaps have the size of a page, they were allocated with kzalloc().
>>
>> Most of the time, kzalloc() allocates aligned blocks of memory, so
>> copy_page() can be used. But when some debug options like SLAB_DEBUG
>> are activated, kzalloc() may return unaligned pointer.
>>
>> On powerpc, memcpy(), copy_page() and other copying functions use
>> 'dcbz' instruction which provides an entire zeroed cacheline to avoid
>> memory read when the intention is to overwrite a full line. Functions
>> like memcpy() are writen to care about partial cachelines at the start
>> and end of the destination, but copy_page() assumes it gets pages. As
>> pages are naturally cache aligned, copy_page() doesn't care about
>> partial lines. This means that when copy_page() is called with a
>> misaligned pointer, a few leading bytes are zeroed.
>>
>> To fix it, allocate bitmaps through kmem_cache instead of using kzalloc()
>> The cache pool is created with PAGE_SIZE alignment constraint.
>>
>> Reported-by: Erhard F. <erhard_f@mailbox.org>
>> Link: https://bugzilla.kernel.org/show_bug.cgi?id=204371
>> Fixes: 69d2480456d1 ("btrfs: use copy_page for copying pages instead of memcpy")
>> Cc: stable@vger.kernel.org
>> Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
>> ---
>> v2: Using kmem_cache instead of get_zeroed_page() in order to benefit from SLAB debugging features like redzone.
>
> I'll take this version, thanks. Though I'm not happy about the allocator
> behaviour. The kmem cache based fix can be backported independently to
> 4.19 regardless of the SL*B fixes.
>
>> +extern struct kmem_cache *btrfs_bitmap_cachep;
>
> I've renamed the cache to btrfs_free_space_bitmap_cachep
>
> Reviewed-by: David Sterba <dsterba@suse.com>
Isn't this obsoleted by
'[PATCH v2 0/2] guarantee natural alignment for kmalloc()' ?
>
^ permalink raw reply
* Re: [PATCH RESEND v11 7/8] open: openat2(2) syscall
From: sbaugh @ 2019-08-26 19:50 UTC (permalink / raw)
To: linuxppc-dev
Cc: linux-arch, linux-ia64, linux-parisc, linux-sh, linux-api,
linux-kernel, linux-mips, linuxppc-dev, sparclinux, linux-alpha,
linux-fsdevel, linux-arm-kernel
In-Reply-To: <20190820033406.29796-8-cyphar@cyphar.com>
Aleksa Sarai <cyphar@cyphar.com> writes:
> To this end, we introduce the openat2(2) syscall. It provides all of the
> features of openat(2) through the @how->flags argument, but also
> also provides a new @how->resolve argument which exposes RESOLVE_* flags
> that map to our new LOOKUP_* flags. It also eliminates the long-standing
> ugliness of variadic-open(2) by embedding it in a struct.
I don't like this usage of a structure in memory to pass arguments that
would fit in registers. This would be quite inconvenient for me as a
userspace developer.
Others have brought up issues with this: the issue of seccomp, and the
issue of mismatch between the userspace interface and the kernel
interface, are the most important for me. I want to add another,
admittedly somewhat niche, concern.
This interfaces requires a program to allocate memory (even on the
stack) just to pass arguments to the kernel which could be passed
without allocating that memory. That makes it more difficult and less
efficient to use this syscall in any case where memory is not so easily
allocatable: such as early program startup or assembly, where the stack
may be limited in size or not even available yet, or when injecting a
syscall while ptracing.
A struct-passing interface was needed for clone, since we ran out of
registers; but we have not run out of registers yet for openat, so it
would be nice to avoid this if we can. We can always expand later...
^ permalink raw reply
* Re: [PATCH v12 00/11] Appended signatures support for IMA appraisal
From: Jordan Hand @ 2019-08-26 22:46 UTC (permalink / raw)
To: Thiago Jung Bauermann, linux-integrity
Cc: Herbert Xu, linux-doc, Dmitry Kasatkin, David S. Miller,
Jonathan Corbet, linux-kernel, Mimi Zohar, James Morris,
David Howells, AKASHI, Takahiro, linux-security-module, keyrings,
linux-crypto, Jessica Yu, linuxppc-dev, David Woodhouse,
Serge E. Hallyn
In-Reply-To: <20190628021934.4260-1-bauerman@linux.ibm.com>
On 6/27/19 7:19 PM, Thiago Jung Bauermann wrote:
> On the OpenPOWER platform, secure boot and trusted boot are being
> implemented using IMA for taking measurements and verifying signatures.
> Since the kernel image on Power servers is an ELF binary, kernels are
> signed using the scripts/sign-file tool and thus use the same signature
> format as signed kernel modules.
>
> This patch series adds support in IMA for verifying those signatures.
> It adds flexibility to OpenPOWER secure boot, because it allows it to boot
> kernels with the signature appended to them as well as kernels where the
> signature is stored in the IMA extended attribute.
I know this is pretty late, but I just wanted to let you know that I
tested this patch set on x86_64 with QEMU.
That is, I enrolled a key to _ima keyring, signed my kernel and modules
with appended signatures (with scripts/sign-file), set the IMA policy to
appraise and measure my kernel and modules. Also tested kexec appraisal.
You can add my tested-by if you'd like.
-Jordan
^ permalink raw reply
* Re: [PATCH kernel v2 2/4] KVM: PPC: Invalidate multiple TCEs at once
From: Paul Mackerras @ 2019-08-27 0:32 UTC (permalink / raw)
To: Alexey Kardashevskiy
Cc: kvm, Alistair Popple, kvm-ppc, Alex Williamson, linuxppc-dev,
David Gibson
In-Reply-To: <20190826061705.92048-3-aik@ozlabs.ru>
On Mon, Aug 26, 2019 at 04:17:03PM +1000, Alexey Kardashevskiy wrote:
> Invalidating a TCE cache entry for each updated TCE is quite expensive.
> This makes use of the new iommu_table_ops::xchg_no_kill()/tce_kill()
> callbacks to bring down the time spent in mapping a huge guest DMA window;
> roughly 20s to 10s for each guest's 100GB of DMA space.
>
> Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
With the addition of "Book3S" to the patch title,
Acked-by: Paul Mackerras <paulus@ozlabs.org>
^ permalink raw reply
* Re: [PATCH v6 00/12] implement KASLR for powerpc/fsl_booke/32
From: Jason Yan @ 2019-08-27 0:39 UTC (permalink / raw)
To: mpe, linuxppc-dev, diana.craciun, christophe.leroy, benh, paulus,
npiggin, keescook, kernel-hardening
Cc: wangkefeng.wang, linux-kernel, jingxiangfeng, zhaohongjiang,
thunder.leizhen, fanchengyang, yebin10
In-Reply-To: <ed96199d-715c-3f1c-39db-10a569ba6601@huawei.com>
A polite ping :)
What else should I do now?
Thanks
On 2019/8/19 14:12, Jason Yan wrote:
> Hi Michael,
>
> Is there anything more I should do to get this feature meeting the
> requirements of the mainline?
>
> Thanks,
> Jason
>
> On 2019/8/9 18:07, Jason Yan wrote:
>> This series implements KASLR for powerpc/fsl_booke/32, as a security
>> feature that deters exploit attempts relying on knowledge of the location
>> of kernel internals.
>>
>> Since CONFIG_RELOCATABLE has already supported, what we need to do is
>> map or copy kernel to a proper place and relocate. Freescale Book-E
>> parts expect lowmem to be mapped by fixed TLB entries(TLB1). The TLB1
>> entries are not suitable to map the kernel directly in a randomized
>> region, so we chose to copy the kernel to a proper place and restart to
>> relocate.
>>
>> Entropy is derived from the banner and timer base, which will change
>> every
>> build and boot. This not so much safe so additionally the bootloader may
>> pass entropy via the /chosen/kaslr-seed node in device tree.
>>
>> We will use the first 512M of the low memory to randomize the kernel
>> image. The memory will be split in 64M zones. We will use the lower 8
>> bit of the entropy to decide the index of the 64M zone. Then we chose a
>> 16K aligned offset inside the 64M zone to put the kernel in.
>>
>> KERNELBASE
>>
>> |--> 64M <--|
>> | |
>> +---------------+ +----------------+---------------+
>> | |....| |kernel| | |
>> +---------------+ +----------------+---------------+
>> | |
>> |-----> offset <-----|
>>
>> kernstart_virt_addr
>>
>> We also check if we will overlap with some areas like the dtb area, the
>> initrd area or the crashkernel area. If we cannot find a proper area,
>> kaslr will be disabled and boot from the original kernel.
>>
>> Changes since v5:
>> - Rename M_IF_NEEDED to MAS2_M_IF_NEEDED
>> - Define some global variable as __ro_after_init
>> - Replace kimage_vaddr with kernstart_virt_addr
>> - Depend on RELOCATABLE, not select it
>> - Modify the comment block below the SPDX tag
>> - Remove some useless headers in kaslr_booke.c and move is_second_reloc
>> declarationto mmu_decl.h
>> - Remove DBG() and use pr_debug() and rewrite comment above
>> get_boot_seed().
>> - Add a patch to document the KASLR implementation.
>> - Split a patch from patch #10 which exports kaslr offset in
>> VMCOREINFO ELF notes.
>> - Remove extra logic around finding nokaslr string in cmdline.
>> - Make regions static global and __initdata
>>
>> Changes since v4:
>> - Add Reviewed-by tag from Christophe
>> - Remove an unnecessary cast
>> - Remove unnecessary parenthesis
>> - Fix checkpatch warning
>>
>> Changes since v3:
>> - Add Reviewed-by and Tested-by tag from Diana
>> - Change the comment in fsl_booke_entry_mapping.S to be consistent
>> with the new code.
>>
>> Changes since v2:
>> - Remove unnecessary #ifdef
>> - Use SZ_64M instead of0x4000000
>> - Call early_init_dt_scan_chosen() to init boot_command_line
>> - Rename kaslr_second_init() to kaslr_late_init()
>>
>> Changes since v1:
>> - Remove some useless 'extern' keyword.
>> - Replace EXPORT_SYMBOL with EXPORT_SYMBOL_GPL
>> - Improve some assembly code
>> - Use memzero_explicit instead of memset
>> - Use boot_command_line and remove early_command_line
>> - Do not print kaslr offset if kaslr is disabled
>>
>> Jason Yan (12):
>> powerpc: unify definition of M_IF_NEEDED
>> powerpc: move memstart_addr and kernstart_addr to init-common.c
>> powerpc: introduce kernstart_virt_addr to store the kernel base
>> powerpc/fsl_booke/32: introduce create_tlb_entry() helper
>> powerpc/fsl_booke/32: introduce reloc_kernel_entry() helper
>> powerpc/fsl_booke/32: implement KASLR infrastructure
>> powerpc/fsl_booke/32: randomize the kernel image offset
>> powerpc/fsl_booke/kaslr: clear the original kernel if randomized
>> powerpc/fsl_booke/kaslr: support nokaslr cmdline parameter
>> powerpc/fsl_booke/kaslr: dump out kernel offset information on panic
>> powerpc/fsl_booke/kaslr: export offset in VMCOREINFO ELF notes
>> powerpc/fsl_booke/32: Document KASLR implementation
>>
>> Documentation/powerpc/kaslr-booke32.rst | 42 ++
>> arch/powerpc/Kconfig | 11 +
>> arch/powerpc/include/asm/nohash/mmu-book3e.h | 10 +
>> arch/powerpc/include/asm/page.h | 7 +
>> arch/powerpc/kernel/Makefile | 1 +
>> arch/powerpc/kernel/early_32.c | 2 +-
>> arch/powerpc/kernel/exceptions-64e.S | 12 +-
>> arch/powerpc/kernel/fsl_booke_entry_mapping.S | 27 +-
>> arch/powerpc/kernel/head_fsl_booke.S | 55 ++-
>> arch/powerpc/kernel/kaslr_booke.c | 393 ++++++++++++++++++
>> arch/powerpc/kernel/machine_kexec.c | 1 +
>> arch/powerpc/kernel/misc_64.S | 7 +-
>> arch/powerpc/kernel/setup-common.c | 20 +
>> arch/powerpc/mm/init-common.c | 7 +
>> arch/powerpc/mm/init_32.c | 5 -
>> arch/powerpc/mm/init_64.c | 5 -
>> arch/powerpc/mm/mmu_decl.h | 11 +
>> arch/powerpc/mm/nohash/fsl_booke.c | 8 +-
>> 18 files changed, 572 insertions(+), 52 deletions(-)
>> create mode 100644 Documentation/powerpc/kaslr-booke32.rst
>> create mode 100644 arch/powerpc/kernel/kaslr_booke.c
>>
^ permalink raw reply
* Re: [PATCH v12 00/11] Appended signatures support for IMA appraisal
From: Thiago Jung Bauermann @ 2019-08-27 1:04 UTC (permalink / raw)
To: Jordan Hand
Cc: Herbert Xu, linux-doc, Dmitry Kasatkin, David S. Miller,
Jonathan Corbet, linux-kernel, Mimi Zohar, James Morris,
David Howells, AKASHI, Takahiro, linux-security-module, keyrings,
linux-crypto, Jessica Yu, linux-integrity, linuxppc-dev,
David Woodhouse, Serge E. Hallyn
In-Reply-To: <9682b5d0-1634-2dd0-2cbb-eb1fa8ba7423@linux.microsoft.com>
Hello Jordan,
Jordan Hand <jorhand@linux.microsoft.com> writes:
> On 6/27/19 7:19 PM, Thiago Jung Bauermann wrote:
>> On the OpenPOWER platform, secure boot and trusted boot are being
>> implemented using IMA for taking measurements and verifying signatures.
>> Since the kernel image on Power servers is an ELF binary, kernels are
>> signed using the scripts/sign-file tool and thus use the same signature
>> format as signed kernel modules.
>>
>> This patch series adds support in IMA for verifying those signatures.
>> It adds flexibility to OpenPOWER secure boot, because it allows it to boot
>> kernels with the signature appended to them as well as kernels where the
>> signature is stored in the IMA extended attribute.
>
> I know this is pretty late, but I just wanted to let you know that I
> tested this patch set on x86_64 with QEMU.
>
> That is, I enrolled a key to _ima keyring, signed my kernel and modules
> with appended signatures (with scripts/sign-file), set the IMA policy to
> appraise and measure my kernel and modules. Also tested kexec appraisal.
>
> You can add my tested-by if you'd like.
Thanks for testing!
--
Thiago Jung Bauermann
IBM Linux Technology Center
^ permalink raw reply
* Re: [PATCH v6 00/12] implement KASLR for powerpc/fsl_booke/32
From: Michael Ellerman @ 2019-08-27 1:33 UTC (permalink / raw)
To: Scott Wood
Cc: wangkefeng.wang, keescook, Jason Yan, kernel-hardening,
linux-kernel, npiggin, jingxiangfeng, diana.craciun, paulus,
zhaohongjiang, thunder.leizhen, fanchengyang, linuxppc-dev,
yebin10
In-Reply-To: <529fd908-42d6-f96f-daa2-9010f3035879@huawei.com>
Jason Yan <yanaijie@huawei.com> writes:
> A polite ping :)
>
> What else should I do now?
That's a good question.
Scott, are you still maintaining FSL bits, and if so any comments? Or
should I take this.
cheers
> On 2019/8/19 14:12, Jason Yan wrote:
>> Hi Michael,
>>
>> Is there anything more I should do to get this feature meeting the
>> requirements of the mainline?
>>
>> Thanks,
>> Jason
>>
>> On 2019/8/9 18:07, Jason Yan wrote:
>>> This series implements KASLR for powerpc/fsl_booke/32, as a security
>>> feature that deters exploit attempts relying on knowledge of the location
>>> of kernel internals.
>>>
>>> Since CONFIG_RELOCATABLE has already supported, what we need to do is
>>> map or copy kernel to a proper place and relocate. Freescale Book-E
>>> parts expect lowmem to be mapped by fixed TLB entries(TLB1). The TLB1
>>> entries are not suitable to map the kernel directly in a randomized
>>> region, so we chose to copy the kernel to a proper place and restart to
>>> relocate.
>>>
>>> Entropy is derived from the banner and timer base, which will change
>>> every
>>> build and boot. This not so much safe so additionally the bootloader may
>>> pass entropy via the /chosen/kaslr-seed node in device tree.
>>>
>>> We will use the first 512M of the low memory to randomize the kernel
>>> image. The memory will be split in 64M zones. We will use the lower 8
>>> bit of the entropy to decide the index of the 64M zone. Then we chose a
>>> 16K aligned offset inside the 64M zone to put the kernel in.
>>>
>>> KERNELBASE
>>>
>>> |--> 64M <--|
>>> | |
>>> +---------------+ +----------------+---------------+
>>> | |....| |kernel| | |
>>> +---------------+ +----------------+---------------+
>>> | |
>>> |-----> offset <-----|
>>>
>>> kernstart_virt_addr
>>>
>>> We also check if we will overlap with some areas like the dtb area, the
>>> initrd area or the crashkernel area. If we cannot find a proper area,
>>> kaslr will be disabled and boot from the original kernel.
>>>
>>> Changes since v5:
>>> - Rename M_IF_NEEDED to MAS2_M_IF_NEEDED
>>> - Define some global variable as __ro_after_init
>>> - Replace kimage_vaddr with kernstart_virt_addr
>>> - Depend on RELOCATABLE, not select it
>>> - Modify the comment block below the SPDX tag
>>> - Remove some useless headers in kaslr_booke.c and move is_second_reloc
>>> declarationto mmu_decl.h
>>> - Remove DBG() and use pr_debug() and rewrite comment above
>>> get_boot_seed().
>>> - Add a patch to document the KASLR implementation.
>>> - Split a patch from patch #10 which exports kaslr offset in
>>> VMCOREINFO ELF notes.
>>> - Remove extra logic around finding nokaslr string in cmdline.
>>> - Make regions static global and __initdata
>>>
>>> Changes since v4:
>>> - Add Reviewed-by tag from Christophe
>>> - Remove an unnecessary cast
>>> - Remove unnecessary parenthesis
>>> - Fix checkpatch warning
>>>
>>> Changes since v3:
>>> - Add Reviewed-by and Tested-by tag from Diana
>>> - Change the comment in fsl_booke_entry_mapping.S to be consistent
>>> with the new code.
>>>
>>> Changes since v2:
>>> - Remove unnecessary #ifdef
>>> - Use SZ_64M instead of0x4000000
>>> - Call early_init_dt_scan_chosen() to init boot_command_line
>>> - Rename kaslr_second_init() to kaslr_late_init()
>>>
>>> Changes since v1:
>>> - Remove some useless 'extern' keyword.
>>> - Replace EXPORT_SYMBOL with EXPORT_SYMBOL_GPL
>>> - Improve some assembly code
>>> - Use memzero_explicit instead of memset
>>> - Use boot_command_line and remove early_command_line
>>> - Do not print kaslr offset if kaslr is disabled
>>>
>>> Jason Yan (12):
>>> powerpc: unify definition of M_IF_NEEDED
>>> powerpc: move memstart_addr and kernstart_addr to init-common.c
>>> powerpc: introduce kernstart_virt_addr to store the kernel base
>>> powerpc/fsl_booke/32: introduce create_tlb_entry() helper
>>> powerpc/fsl_booke/32: introduce reloc_kernel_entry() helper
>>> powerpc/fsl_booke/32: implement KASLR infrastructure
>>> powerpc/fsl_booke/32: randomize the kernel image offset
>>> powerpc/fsl_booke/kaslr: clear the original kernel if randomized
>>> powerpc/fsl_booke/kaslr: support nokaslr cmdline parameter
>>> powerpc/fsl_booke/kaslr: dump out kernel offset information on panic
>>> powerpc/fsl_booke/kaslr: export offset in VMCOREINFO ELF notes
>>> powerpc/fsl_booke/32: Document KASLR implementation
>>>
>>> Documentation/powerpc/kaslr-booke32.rst | 42 ++
>>> arch/powerpc/Kconfig | 11 +
>>> arch/powerpc/include/asm/nohash/mmu-book3e.h | 10 +
>>> arch/powerpc/include/asm/page.h | 7 +
>>> arch/powerpc/kernel/Makefile | 1 +
>>> arch/powerpc/kernel/early_32.c | 2 +-
>>> arch/powerpc/kernel/exceptions-64e.S | 12 +-
>>> arch/powerpc/kernel/fsl_booke_entry_mapping.S | 27 +-
>>> arch/powerpc/kernel/head_fsl_booke.S | 55 ++-
>>> arch/powerpc/kernel/kaslr_booke.c | 393 ++++++++++++++++++
>>> arch/powerpc/kernel/machine_kexec.c | 1 +
>>> arch/powerpc/kernel/misc_64.S | 7 +-
>>> arch/powerpc/kernel/setup-common.c | 20 +
>>> arch/powerpc/mm/init-common.c | 7 +
>>> arch/powerpc/mm/init_32.c | 5 -
>>> arch/powerpc/mm/init_64.c | 5 -
>>> arch/powerpc/mm/mmu_decl.h | 11 +
>>> arch/powerpc/mm/nohash/fsl_booke.c | 8 +-
>>> 18 files changed, 572 insertions(+), 52 deletions(-)
>>> create mode 100644 Documentation/powerpc/kaslr-booke32.rst
>>> create mode 100644 arch/powerpc/kernel/kaslr_booke.c
>>>
^ permalink raw reply
* Re: [PATCH v2] powerpc: Allow flush_(inval_)dcache_range to work across ranges >4GB
From: Michael Ellerman @ 2019-08-27 1:50 UTC (permalink / raw)
To: Alastair D'Silva, alastair
Cc: linux-kernel, stable, Paul Mackerras, Greg Kroah-Hartman,
Thomas Gleixner, linuxppc-dev, Allison Randal
In-Reply-To: <20190821001929.4253-1-alastair@au1.ibm.com>
"Alastair D'Silva" <alastair@au1.ibm.com> writes:
> From: Alastair D'Silva <alastair@d-silva.org>
>
> The upstream commit:
> 22e9c88d486a ("powerpc/64: reuse PPC32 static inline flush_dcache_range()")
> has a similar effect, but since it is a rewrite of the assembler to C, is
> too invasive for stable. This patch is a minimal fix to address the issue in
> assembler.
>
> This patch applies cleanly to v5.2, v4.19 & v4.14.
>
> When calling flush_(inval_)dcache_range with a size >4GB, we were masking
> off the upper 32 bits, so we would incorrectly flush a range smaller
> than intended.
>
> This patch replaces the 32 bit shifts with 64 bit ones, so that
> the full size is accounted for.
>
> Changelog:
> v2
> - Add related upstream commit
>
> Signed-off-by: Alastair D'Silva <alastair@d-silva.org>
> ---
> arch/powerpc/kernel/misc_64.S | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
cheers
> diff --git a/arch/powerpc/kernel/misc_64.S b/arch/powerpc/kernel/misc_64.S
> index 1ad4089dd110..d4d096f80f4b 100644
> --- a/arch/powerpc/kernel/misc_64.S
> +++ b/arch/powerpc/kernel/misc_64.S
> @@ -130,7 +130,7 @@ _GLOBAL_TOC(flush_dcache_range)
> subf r8,r6,r4 /* compute length */
> add r8,r8,r5 /* ensure we get enough */
> lwz r9,DCACHEL1LOGBLOCKSIZE(r10) /* Get log-2 of dcache block size */
> - srw. r8,r8,r9 /* compute line count */
> + srd. r8,r8,r9 /* compute line count */
> beqlr /* nothing to do? */
> mtctr r8
> 0: dcbst 0,r6
> @@ -148,7 +148,7 @@ _GLOBAL(flush_inval_dcache_range)
> subf r8,r6,r4 /* compute length */
> add r8,r8,r5 /* ensure we get enough */
> lwz r9,DCACHEL1LOGBLOCKSIZE(r10)/* Get log-2 of dcache block size */
> - srw. r8,r8,r9 /* compute line count */
> + srd. r8,r8,r9 /* compute line count */
> beqlr /* nothing to do? */
> sync
> isync
> --
> 2.21.0
^ permalink raw reply
* Re: [PATCH v2] btrfs: fix allocation of bitmap pages.
From: Michael Ellerman @ 2019-08-27 1:54 UTC (permalink / raw)
To: David Sterba, Nikolay Borisov
Cc: erhard_f, linux-mm, linux-kernel, Josef Bacik, stable, dsterba,
Chris Mason, David Sterba, Andrew Morton, linuxppc-dev,
linux-btrfs
In-Reply-To: <20190826164646.GX2752@twin.jikos.cz>
David Sterba <dsterba@suse.cz> writes:
> On Mon, Aug 26, 2019 at 06:40:24PM +0300, Nikolay Borisov wrote:
>> >> Link: https://bugzilla.kernel.org/show_bug.cgi?id=204371
>> >> Fixes: 69d2480456d1 ("btrfs: use copy_page for copying pages instead of memcpy")
>> >> Cc: stable@vger.kernel.org
>> >> Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
>> >> ---
>> >> v2: Using kmem_cache instead of get_zeroed_page() in order to benefit from SLAB debugging features like redzone.
>> >
>> > I'll take this version, thanks. Though I'm not happy about the allocator
>> > behaviour. The kmem cache based fix can be backported independently to
>> > 4.19 regardless of the SL*B fixes.
>> >
>> >> +extern struct kmem_cache *btrfs_bitmap_cachep;
>> >
>> > I've renamed the cache to btrfs_free_space_bitmap_cachep
>> >
>> > Reviewed-by: David Sterba <dsterba@suse.com>
>>
>> Isn't this obsoleted by
>>
>> '[PATCH v2 0/2] guarantee natural alignment for kmalloc()' ?
>
> Yeah, but this would add maybe another whole dev cycle to merge and
> release. The reporters of the bug seem to care enough to identify the
> problem and propose the fix so I feel like adding the btrfs-specific fix
> now is a little favor we can afford.
>
> The bug is reproduced on an architecture that's not widely tested so
> from practical POV I think this adds more coverage which is desirable.
Thanks.
cheers
^ permalink raw reply
* Re: [PATCH] powerpc/time: use feature fixup in __USE_RTC() instead of cpu feature.
From: Michael Ellerman @ 2019-08-27 2:12 UTC (permalink / raw)
To: Benjamin Herrenschmidt, Christophe Leroy, Paul Mackerras
Cc: linuxppc-dev, linux-kernel
In-Reply-To: <60da7620a43dc29317a062f1d58dcfde8d32b258.camel@kernel.crashing.org>
Benjamin Herrenschmidt <benh@kernel.crashing.org> writes:
> On Mon, 2019-08-26 at 21:41 +1000, Michael Ellerman wrote:
>> Christophe Leroy <christophe.leroy@c-s.fr> writes:
>> > sched_clock(), used by printk(), calls __USE_RTC() to know
>> > whether to use realtime clock or timebase.
>> >
>> > __USE_RTC() uses cpu_has_feature() which is initialised by
>> > machine_init(). Before machine_init(), __USE_RTC() returns true,
>> > leading to a program check exception on CPUs not having realtime
>> > clock.
>> >
>> > In order to be able to use printk() earlier, use feature fixup.
>> > Feature fixups are applies in early_init(), enabling the use of
>> > printk() earlier.
>> >
>> > Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
>> > ---
>> > arch/powerpc/include/asm/time.h | 9 ++++++++-
>> > 1 file changed, 8 insertions(+), 1 deletion(-)
>>
>> The other option would be just to make this a compile time decision, eg.
>> add CONFIG_PPC_601 and use that to gate whether we use RTC.
>>
>> Given how many 601 users there are, maybe 1?, I think that would be a
>> simpler option and avoids complicating the code / binary for everyone
>> else.
>
> Didn't we ditch 601 support years ago anyway ? We had workaround we
> threw out I think...
Paul said his still booted recently.
cheers
^ permalink raw reply
* Re: [PATCH] powerpc/time: use feature fixup in __USE_RTC() instead of cpu feature.
From: Michael Ellerman @ 2019-08-27 2:13 UTC (permalink / raw)
To: Christophe Leroy, Benjamin Herrenschmidt, Paul Mackerras
Cc: linuxppc-dev, linux-kernel
In-Reply-To: <ba2a7a1f-8dcc-ec44-81d4-ef11a9e29377@c-s.fr>
Christophe Leroy <christophe.leroy@c-s.fr> writes:
> Le 26/08/2019 à 13:41, Michael Ellerman a écrit :
>> Christophe Leroy <christophe.leroy@c-s.fr> writes:
>>> sched_clock(), used by printk(), calls __USE_RTC() to know
>>> whether to use realtime clock or timebase.
>>>
>>> __USE_RTC() uses cpu_has_feature() which is initialised by
>>> machine_init(). Before machine_init(), __USE_RTC() returns true,
>>> leading to a program check exception on CPUs not having realtime
>>> clock.
>>>
>>> In order to be able to use printk() earlier, use feature fixup.
>>> Feature fixups are applies in early_init(), enabling the use of
>>> printk() earlier.
>>>
>>> Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
>>> ---
>>> arch/powerpc/include/asm/time.h | 9 ++++++++-
>>> 1 file changed, 8 insertions(+), 1 deletion(-)
>>
>> The other option would be just to make this a compile time decision, eg.
>> add CONFIG_PPC_601 and use that to gate whether we use RTC.
>
> Euh ... yes OK, why not. And that would help simplify many places in the
> code. I can propose something in that direction, but it will be a bigger
> change.
Thanks.
>> Given how many 601 users there are, maybe 1?, I think that would be a
>> simpler option and avoids complicating the code / binary for everyone
>> else.
>
> However this patch doesn't complicate things more than it was with
> cpu_has_feature() which does exactly the same but using static keys,
> does it ?
It's more complicated in that it's not using cpu_has_feature() it's
doing some custom thing that is not used anywhere else. But yeah I guess
it's not much extra complication.
cheers
^ permalink raw reply
* Re: [PATCH v3] powerpc/fadump: sysfs for fadump memory reservation
From: Michael Ellerman @ 2019-08-27 3:19 UTC (permalink / raw)
To: Hari Bathini, Sourabh Jain
Cc: corbet, mahesh, linux-doc, linux-kernel, gregkh, linuxppc-dev
In-Reply-To: <f8e9cbdd-1926-081d-c8e6-f9d55408fe51@linux.ibm.com>
Hari Bathini <hbathini@linux.ibm.com> writes:
> On 26/08/19 4:14 PM, Sourabh Jain wrote:
>> On 8/26/19 3:46 PM, Sourabh Jain wrote:
>>> On 8/26/19 3:29 PM, Hari Bathini wrote:
>>>> On 10/08/19 11:29 PM, Sourabh Jain wrote:
>>>>> Add a sys interface to allow querying the memory reserved by
>>>>> fadump for saving the crash dump.
>>>>>
>>>>> Add an ABI doc entry for new sysfs interface.
>>>>> - /sys/kernel/fadump_mem_reserved
>>>>>
>>>>> Signed-off-by: Sourabh Jain <sourabhjain@linux.ibm.com>
>>>>> ---
>>>>> Changelog:
>>>>> v1 -> v2:
>>>>> - Added ABI doc for new sysfs interface.
>>>>>
>>>>> v2 -> v3:
>>>>> - Updated the ABI documentation.
>>>>> ---
>>>>>
>>>>> Documentation/ABI/testing/sysfs-kernel-fadump | 6 ++++++
>>>>
>>>> Shouldn't this be Documentation/ABI/testing/sysfs-kernel-fadump_mem_reserved?
>>
>> How about documenting fadump_mem_reserved and other sysfs attributes suggested
>> by you in a single file Documentation/ABI/testing/sysfs-kernel-fadump?
>
> I wouldn't mind that but please do check if it is breaking a convention..
AIUI a file named like that would hold the documentation for the files
inside a directory called /sys/kernel/fadump.
And in fact that's probably where these files should live, rather than
just dropped directly into /sys/kernel.
cheers
^ permalink raw reply
* [PATCH 0/4] powerpc/64: syscalls in C
From: Nicholas Piggin @ 2019-08-27 3:30 UTC (permalink / raw)
To: linuxppc-dev; +Cc: Nicholas Piggin
This hasn't been highly stress tested or tested all cases (like 32-bit
binaries, single stepping, etc.) but so far it's running stable doing
normal kernel development and microbenchmarks.
Thanks,
Nick
Nicholas Piggin (4):
powerpc: convert to copy_thread_tls
powerpc/64: remove support for kernel-mode syscalls
powerpc/64: system call remove non-volatile GPR save optimisation
powerpc/64: system call implement the bulk of the logic in C
arch/powerpc/Kconfig | 1 +
arch/powerpc/include/asm/asm-prototypes.h | 11 -
arch/powerpc/include/asm/ptrace.h | 3 +
arch/powerpc/include/asm/signal.h | 2 +
arch/powerpc/include/asm/switch_to.h | 4 +
arch/powerpc/include/asm/time.h | 3 +
arch/powerpc/kernel/Makefile | 3 +-
arch/powerpc/kernel/entry_64.S | 424 ++++------------------
arch/powerpc/kernel/exceptions-64s.S | 2 -
arch/powerpc/kernel/process.c | 15 +-
arch/powerpc/kernel/signal.h | 2 -
arch/powerpc/kernel/syscall_64.c | 202 +++++++++++
arch/powerpc/kernel/syscalls/syscall.tbl | 22 +-
13 files changed, 305 insertions(+), 389 deletions(-)
create mode 100644 arch/powerpc/kernel/syscall_64.c
--
2.22.0
^ permalink raw reply
* [PATCH 1/4] powerpc: convert to copy_thread_tls
From: Nicholas Piggin @ 2019-08-27 3:30 UTC (permalink / raw)
To: linuxppc-dev; +Cc: Nicholas Piggin
In-Reply-To: <20190827033010.28090-1-npiggin@gmail.com>
Commit 3033f14ab78c3 ("clone: support passing tls argument via C rather
than pt_regs magic") introduced the HAVE_COPY_THREAD_TLS option. Use it
to avoid a subtle assumption about the argument ordering of clone type
syscalls.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---
arch/powerpc/Kconfig | 1 +
arch/powerpc/kernel/process.c | 9 +++++----
2 files changed, 6 insertions(+), 4 deletions(-)
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index d8dcd8820369..7477a3263225 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -182,6 +182,7 @@ config PPC
select HAVE_STACKPROTECTOR if PPC64 && $(cc-option,-mstack-protector-guard=tls -mstack-protector-guard-reg=r13)
select HAVE_STACKPROTECTOR if PPC32 && $(cc-option,-mstack-protector-guard=tls -mstack-protector-guard-reg=r2)
select HAVE_CONTEXT_TRACKING if PPC64
+ select HAVE_COPY_THREAD_TLS
select HAVE_DEBUG_KMEMLEAK
select HAVE_DEBUG_STACKOVERFLOW
select HAVE_DYNAMIC_FTRACE
diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
index 8fc4de0d22b4..24621e7e5033 100644
--- a/arch/powerpc/kernel/process.c
+++ b/arch/powerpc/kernel/process.c
@@ -1600,8 +1600,9 @@ static void setup_ksp_vsid(struct task_struct *p, unsigned long sp)
/*
* Copy architecture-specific thread state
*/
-int copy_thread(unsigned long clone_flags, unsigned long usp,
- unsigned long kthread_arg, struct task_struct *p)
+int copy_thread_tls(unsigned long clone_flags, unsigned long usp,
+ unsigned long kthread_arg, struct task_struct *p,
+ unsigned long tls)
{
struct pt_regs *childregs, *kregs;
extern void ret_from_fork(void);
@@ -1642,10 +1643,10 @@ int copy_thread(unsigned long clone_flags, unsigned long usp,
if (clone_flags & CLONE_SETTLS) {
#ifdef CONFIG_PPC64
if (!is_32bit_task())
- childregs->gpr[13] = childregs->gpr[6];
+ childregs->gpr[13] = tls;
else
#endif
- childregs->gpr[2] = childregs->gpr[6];
+ childregs->gpr[2] = tls;
}
f = ret_from_fork;
--
2.22.0
^ permalink raw reply related
* [PATCH 2/4] powerpc/64: remove support for kernel-mode syscalls
From: Nicholas Piggin @ 2019-08-27 3:30 UTC (permalink / raw)
To: linuxppc-dev; +Cc: Nicholas Piggin
In-Reply-To: <20190827033010.28090-1-npiggin@gmail.com>
There is support for the kernel to execute the 'sc 0' instruction and
make a system call to itself. This is a relic that is unused in the
tree, therefore untested. It's also highly questionable for modules to
be doing this.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---
arch/powerpc/kernel/entry_64.S | 21 ++++++---------------
arch/powerpc/kernel/exceptions-64s.S | 2 --
2 files changed, 6 insertions(+), 17 deletions(-)
diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S
index 0a0b5310f54a..6467bdab8d40 100644
--- a/arch/powerpc/kernel/entry_64.S
+++ b/arch/powerpc/kernel/entry_64.S
@@ -69,24 +69,20 @@ BEGIN_FTR_SECTION
bne .Ltabort_syscall
END_FTR_SECTION_IFSET(CPU_FTR_TM)
#endif
- andi. r10,r12,MSR_PR
mr r10,r1
- addi r1,r1,-INT_FRAME_SIZE
- beq- 1f
ld r1,PACAKSAVE(r13)
-1: std r10,0(r1)
+ std r10,0(r1)
std r11,_NIP(r1)
std r12,_MSR(r1)
std r0,GPR0(r1)
std r10,GPR1(r1)
- beq 2f /* if from kernel mode */
#ifdef CONFIG_PPC_FSL_BOOK3E
START_BTB_FLUSH_SECTION
BTB_FLUSH(r10)
END_BTB_FLUSH_SECTION
#endif
ACCOUNT_CPU_USER_ENTRY(r13, r10, r11)
-2: std r2,GPR2(r1)
+ std r2,GPR2(r1)
std r3,GPR3(r1)
mfcr r2
std r4,GPR4(r1)
@@ -122,14 +118,13 @@ END_BTB_FLUSH_SECTION
#if defined(CONFIG_VIRT_CPU_ACCOUNTING_NATIVE) && defined(CONFIG_PPC_SPLPAR)
BEGIN_FW_FTR_SECTION
- beq 33f
- /* if from user, see if there are any DTL entries to process */
+ /* see if there are any DTL entries to process */
ld r10,PACALPPACAPTR(r13) /* get ptr to VPA */
ld r11,PACA_DTL_RIDX(r13) /* get log read index */
addi r10,r10,LPPACA_DTLIDX
LDX_BE r10,0,r10 /* get log write index */
- cmpd cr1,r11,r10
- beq+ cr1,33f
+ cmpd r11,r10
+ beq+ 33f
bl accumulate_stolen_time
REST_GPR(0,r1)
REST_4GPRS(3,r1)
@@ -203,6 +198,7 @@ system_call: /* label this so stack traces look sane */
mtctr r12
bctrl /* Call handler */
+ /* syscall_exit can exit to kernel mode, via ret_from_kernel_thread */
.Lsyscall_exit:
std r3,RESULT(r1)
@@ -216,11 +212,6 @@ system_call: /* label this so stack traces look sane */
ld r12, PACA_THREAD_INFO(r13)
ld r8,_MSR(r1)
-#ifdef CONFIG_PPC_BOOK3S
- /* No MSR:RI on BookE */
- andi. r10,r8,MSR_RI
- beq- .Lunrecov_restore
-#endif
/*
* This is a few instructions into the actual syscall exit path (which actually
diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S
index 6ba3cc2ef8ab..768f133de4f1 100644
--- a/arch/powerpc/kernel/exceptions-64s.S
+++ b/arch/powerpc/kernel/exceptions-64s.S
@@ -1521,8 +1521,6 @@ EXC_COMMON(trap_0b_common, 0xb00, unknown_exception)
* system call / hypercall (0xc00, 0x4c00)
*
* The system call exception is invoked with "sc 0" and does not alter HV bit.
- * There is support for kernel code to invoke system calls but there are no
- * in-tree users.
*
* The hypercall is invoked with "sc 1" and sets HV=1.
*
--
2.22.0
^ permalink raw reply related
* [PATCH 2/4] powerpc/64s: remove support for kernel-mode syscalls
From: Nicholas Piggin @ 2019-08-27 3:30 UTC (permalink / raw)
To: linuxppc-dev; +Cc: Nicholas Piggin
In-Reply-To: <20190827033010.28090-1-npiggin@gmail.com>
There is support for the kernel to execute the 'sc 0' instruction and
make a system call to itself. This is a relic that is unused in the
tree, therefore untested. It's also highly questionable for modules to
be doing this.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---
arch/powerpc/kernel/entry_64.S | 21 ++++++---------------
arch/powerpc/kernel/exceptions-64s.S | 2 --
2 files changed, 6 insertions(+), 17 deletions(-)
diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S
index 0a0b5310f54a..6467bdab8d40 100644
--- a/arch/powerpc/kernel/entry_64.S
+++ b/arch/powerpc/kernel/entry_64.S
@@ -69,24 +69,20 @@ BEGIN_FTR_SECTION
bne .Ltabort_syscall
END_FTR_SECTION_IFSET(CPU_FTR_TM)
#endif
- andi. r10,r12,MSR_PR
mr r10,r1
- addi r1,r1,-INT_FRAME_SIZE
- beq- 1f
ld r1,PACAKSAVE(r13)
-1: std r10,0(r1)
+ std r10,0(r1)
std r11,_NIP(r1)
std r12,_MSR(r1)
std r0,GPR0(r1)
std r10,GPR1(r1)
- beq 2f /* if from kernel mode */
#ifdef CONFIG_PPC_FSL_BOOK3E
START_BTB_FLUSH_SECTION
BTB_FLUSH(r10)
END_BTB_FLUSH_SECTION
#endif
ACCOUNT_CPU_USER_ENTRY(r13, r10, r11)
-2: std r2,GPR2(r1)
+ std r2,GPR2(r1)
std r3,GPR3(r1)
mfcr r2
std r4,GPR4(r1)
@@ -122,14 +118,13 @@ END_BTB_FLUSH_SECTION
#if defined(CONFIG_VIRT_CPU_ACCOUNTING_NATIVE) && defined(CONFIG_PPC_SPLPAR)
BEGIN_FW_FTR_SECTION
- beq 33f
- /* if from user, see if there are any DTL entries to process */
+ /* see if there are any DTL entries to process */
ld r10,PACALPPACAPTR(r13) /* get ptr to VPA */
ld r11,PACA_DTL_RIDX(r13) /* get log read index */
addi r10,r10,LPPACA_DTLIDX
LDX_BE r10,0,r10 /* get log write index */
- cmpd cr1,r11,r10
- beq+ cr1,33f
+ cmpd r11,r10
+ beq+ 33f
bl accumulate_stolen_time
REST_GPR(0,r1)
REST_4GPRS(3,r1)
@@ -203,6 +198,7 @@ system_call: /* label this so stack traces look sane */
mtctr r12
bctrl /* Call handler */
+ /* syscall_exit can exit to kernel mode, via ret_from_kernel_thread */
.Lsyscall_exit:
std r3,RESULT(r1)
@@ -216,11 +212,6 @@ system_call: /* label this so stack traces look sane */
ld r12, PACA_THREAD_INFO(r13)
ld r8,_MSR(r1)
-#ifdef CONFIG_PPC_BOOK3S
- /* No MSR:RI on BookE */
- andi. r10,r8,MSR_RI
- beq- .Lunrecov_restore
-#endif
/*
* This is a few instructions into the actual syscall exit path (which actually
diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S
index 6ba3cc2ef8ab..768f133de4f1 100644
--- a/arch/powerpc/kernel/exceptions-64s.S
+++ b/arch/powerpc/kernel/exceptions-64s.S
@@ -1521,8 +1521,6 @@ EXC_COMMON(trap_0b_common, 0xb00, unknown_exception)
* system call / hypercall (0xc00, 0x4c00)
*
* The system call exception is invoked with "sc 0" and does not alter HV bit.
- * There is support for kernel code to invoke system calls but there are no
- * in-tree users.
*
* The hypercall is invoked with "sc 1" and sets HV=1.
*
--
2.22.0
^ permalink raw reply related
* [PATCH 3/4] powerpc/64: system call remove non-volatile GPR save optimisation
From: Nicholas Piggin @ 2019-08-27 3:30 UTC (permalink / raw)
To: linuxppc-dev; +Cc: Nicholas Piggin
In-Reply-To: <20190827033010.28090-1-npiggin@gmail.com>
powerpc has an optimisation where interrupts avoid saving the
non-volatile (or callee saved) registers to the interrupt stack frame if
they are not required.
Two problems with this are that an interrupt does not always know
whether it will need non-volatiles; and if it does need them, they can
only be saved from the entry-scoped asm code (because we don't control
what the C compiler does with these registers).
system calls are about the worst example of this, some system calls
always require all registers (e.g., fork, to copy regs into the child).
Sometimes registers are only required under certain conditions (e.g.,
tracing, signal delivery). This causes weird ugly logic in the call
chains (e.g., ppc_fork), and also prevents moving substantial amounts
of logic to C.
Remove this optimisation for system calls, and always save NVGPRs on
entry. On modern CPUs this doesn't appear to be worth the complexity
because the stores can be hidden by other work quite well the null
syscall selftests benchmark on a POWER9 has (124.40ns before and
123.64ns after, i.e., well within the noise).
Other interrupts are a little less complex in NVGPR handling, many
do less work at entry and also they don't have as clear a fast path
for avoiding the GPR restore as system calls, so this patch does not
remove the facility completely until more tests can be done.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---
arch/powerpc/kernel/entry_64.S | 72 +++++-------------------
arch/powerpc/kernel/syscalls/syscall.tbl | 22 +++++---
2 files changed, 28 insertions(+), 66 deletions(-)
diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S
index 6467bdab8d40..5a3e0b5c9ad1 100644
--- a/arch/powerpc/kernel/entry_64.S
+++ b/arch/powerpc/kernel/entry_64.S
@@ -98,13 +98,14 @@ END_BTB_FLUSH_SECTION
std r11,_XER(r1)
std r11,_CTR(r1)
std r9,GPR13(r1)
+ SAVE_NVGPRS(r1)
mflr r10
/*
* This clears CR0.SO (bit 28), which is the error indication on
* return from this system call.
*/
rldimi r2,r11,28,(63-28)
- li r11,0xc01
+ li r11,0xc00
std r10,_LINK(r1)
std r11,_TRAP(r1)
std r3,ORIG_GPR3(r1)
@@ -323,7 +324,6 @@ END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR)
/* Traced system call support */
.Lsyscall_dotrace:
- bl save_nvgprs
addi r3,r1,STACK_FRAME_OVERHEAD
bl do_syscall_trace_enter
@@ -408,7 +408,6 @@ END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR)
mtmsrd r10,1
#endif /* CONFIG_PPC_BOOK3E */
- bl save_nvgprs
addi r3,r1,STACK_FRAME_OVERHEAD
bl do_syscall_trace_leave
b ret_from_except
@@ -442,62 +441,6 @@ END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR)
_ASM_NOKPROBE_SYMBOL(system_call_common);
_ASM_NOKPROBE_SYMBOL(system_call_exit);
-/* Save non-volatile GPRs, if not already saved. */
-_GLOBAL(save_nvgprs)
- ld r11,_TRAP(r1)
- andi. r0,r11,1
- beqlr-
- SAVE_NVGPRS(r1)
- clrrdi r0,r11,1
- std r0,_TRAP(r1)
- blr
-_ASM_NOKPROBE_SYMBOL(save_nvgprs);
-
-
-/*
- * The sigsuspend and rt_sigsuspend system calls can call do_signal
- * and thus put the process into the stopped state where we might
- * want to examine its user state with ptrace. Therefore we need
- * to save all the nonvolatile registers (r14 - r31) before calling
- * the C code. Similarly, fork, vfork and clone need the full
- * register state on the stack so that it can be copied to the child.
- */
-
-_GLOBAL(ppc_fork)
- bl save_nvgprs
- bl sys_fork
- b .Lsyscall_exit
-
-_GLOBAL(ppc_vfork)
- bl save_nvgprs
- bl sys_vfork
- b .Lsyscall_exit
-
-_GLOBAL(ppc_clone)
- bl save_nvgprs
- bl sys_clone
- b .Lsyscall_exit
-
-_GLOBAL(ppc_clone3)
- bl save_nvgprs
- bl sys_clone3
- b .Lsyscall_exit
-
-_GLOBAL(ppc32_swapcontext)
- bl save_nvgprs
- bl compat_sys_swapcontext
- b .Lsyscall_exit
-
-_GLOBAL(ppc64_swapcontext)
- bl save_nvgprs
- bl sys_swapcontext
- b .Lsyscall_exit
-
-_GLOBAL(ppc_switch_endian)
- bl save_nvgprs
- bl sys_switch_endian
- b .Lsyscall_exit
-
_GLOBAL(ret_from_fork)
bl schedule_tail
REST_NVGPRS(r1)
@@ -516,6 +459,17 @@ _GLOBAL(ret_from_kernel_thread)
li r3,0
b .Lsyscall_exit
+/* Save non-volatile GPRs, if not already saved. */
+_GLOBAL(save_nvgprs)
+ ld r11,_TRAP(r1)
+ andi. r0,r11,1
+ beqlr-
+ SAVE_NVGPRS(r1)
+ clrrdi r0,r11,1
+ std r0,_TRAP(r1)
+ blr
+_ASM_NOKPROBE_SYMBOL(save_nvgprs);
+
#ifdef CONFIG_PPC_BOOK3S_64
#define FLUSH_COUNT_CACHE \
diff --git a/arch/powerpc/kernel/syscalls/syscall.tbl b/arch/powerpc/kernel/syscalls/syscall.tbl
index 43f736ed47f2..010b9f445586 100644
--- a/arch/powerpc/kernel/syscalls/syscall.tbl
+++ b/arch/powerpc/kernel/syscalls/syscall.tbl
@@ -9,7 +9,9 @@
#
0 nospu restart_syscall sys_restart_syscall
1 nospu exit sys_exit
-2 nospu fork ppc_fork
+2 32 fork ppc_fork sys_fork
+2 64 fork sys_fork
+2 spu fork sys_ni_syscall
3 common read sys_read
4 common write sys_write
5 common open sys_open compat_sys_open
@@ -158,7 +160,9 @@
119 32 sigreturn sys_sigreturn compat_sys_sigreturn
119 64 sigreturn sys_ni_syscall
119 spu sigreturn sys_ni_syscall
-120 nospu clone ppc_clone
+120 32 clone ppc_clone sys_clone
+120 64 clone sys_clone
+120 spu clone sys_ni_syscall
121 common setdomainname sys_setdomainname
122 common uname sys_newuname
123 common modify_ldt sys_ni_syscall
@@ -240,7 +244,9 @@
186 spu sendfile sys_sendfile64
187 common getpmsg sys_ni_syscall
188 common putpmsg sys_ni_syscall
-189 nospu vfork ppc_vfork
+189 32 vfork ppc_vfork sys_vfork
+189 64 vfork sys_vfork
+189 spu vfork sys_ni_syscall
190 common ugetrlimit sys_getrlimit compat_sys_getrlimit
191 common readahead sys_readahead compat_sys_readahead
192 32 mmap2 sys_mmap2 compat_sys_mmap2
@@ -316,8 +322,8 @@
248 32 clock_nanosleep sys_clock_nanosleep_time32
248 64 clock_nanosleep sys_clock_nanosleep
248 spu clock_nanosleep sys_clock_nanosleep
-249 32 swapcontext ppc_swapcontext ppc32_swapcontext
-249 64 swapcontext ppc64_swapcontext
+249 32 swapcontext ppc_swapcontext compat_sys_swapcontext
+249 64 swapcontext sys_swapcontext
249 spu swapcontext sys_ni_syscall
250 common tgkill sys_tgkill
251 32 utimes sys_utimes_time32
@@ -456,7 +462,7 @@
361 common bpf sys_bpf
362 nospu execveat sys_execveat compat_sys_execveat
363 32 switch_endian sys_ni_syscall
-363 64 switch_endian ppc_switch_endian
+363 64 switch_endian sys_switch_endian
363 spu switch_endian sys_ni_syscall
364 common userfaultfd sys_userfaultfd
365 common membarrier sys_membarrier
@@ -516,4 +522,6 @@
432 common fsmount sys_fsmount
433 common fspick sys_fspick
434 common pidfd_open sys_pidfd_open
-435 nospu clone3 ppc_clone3
+435 32 clone3 ppc_clone3 sys_clone3
+435 64 clone3 sys_clone3
+435 nospu clone3 sys_ni_syscall
--
2.22.0
^ permalink raw reply related
* [PATCH 4/4] powerpc/64: system call implement the bulk of the logic in C
From: Nicholas Piggin @ 2019-08-27 3:30 UTC (permalink / raw)
To: linuxppc-dev; +Cc: Nicholas Piggin
In-Reply-To: <20190827033010.28090-1-npiggin@gmail.com>
System call entry and particularly exit code is beyond the limit of what
is reasonable to implement in asm.
This conversion moves all conditional branches out of the asm code,
except a relatively simple test to see whether all GPRs should be
restored at exit time.
Null syscall test is about 5% faster after this patch, because the exit
work is handled under local_irq_disable, and the hard mask and pending
interrupt replay is handled after that, which avoids games with MSR.
The asm instruction scheduling has not really been analysed and
optimised yet, as there are higher level features and improvements to
add first.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---
arch/powerpc/include/asm/asm-prototypes.h | 11 -
arch/powerpc/include/asm/ptrace.h | 3 +
arch/powerpc/include/asm/signal.h | 2 +
arch/powerpc/include/asm/switch_to.h | 4 +
arch/powerpc/include/asm/time.h | 3 +
arch/powerpc/kernel/Makefile | 3 +-
arch/powerpc/kernel/entry_64.S | 343 ++++------------------
arch/powerpc/kernel/process.c | 6 +-
arch/powerpc/kernel/signal.h | 2 -
arch/powerpc/kernel/syscall_64.c | 202 +++++++++++++
10 files changed, 271 insertions(+), 308 deletions(-)
create mode 100644 arch/powerpc/kernel/syscall_64.c
diff --git a/arch/powerpc/include/asm/asm-prototypes.h b/arch/powerpc/include/asm/asm-prototypes.h
index ec1c97a8e8cb..f00ef8924a99 100644
--- a/arch/powerpc/include/asm/asm-prototypes.h
+++ b/arch/powerpc/include/asm/asm-prototypes.h
@@ -92,14 +92,6 @@ long sys_switch_endian(void);
notrace unsigned int __check_irq_replay(void);
void notrace restore_interrupts(void);
-/* ptrace */
-long do_syscall_trace_enter(struct pt_regs *regs);
-void do_syscall_trace_leave(struct pt_regs *regs);
-
-/* process */
-void restore_math(struct pt_regs *regs);
-void restore_tm_state(struct pt_regs *regs);
-
/* prom_init (OpenFirmware) */
unsigned long __init prom_init(unsigned long r3, unsigned long r4,
unsigned long pp,
@@ -110,9 +102,6 @@ unsigned long __init prom_init(unsigned long r3, unsigned long r4,
void __init early_setup(unsigned long dt_ptr);
void early_setup_secondary(void);
-/* time */
-void accumulate_stolen_time(void);
-
/* misc runtime */
extern u64 __bswapdi2(u64);
extern s64 __lshrdi3(s64, int);
diff --git a/arch/powerpc/include/asm/ptrace.h b/arch/powerpc/include/asm/ptrace.h
index feee1b21bbd5..af363086403a 100644
--- a/arch/powerpc/include/asm/ptrace.h
+++ b/arch/powerpc/include/asm/ptrace.h
@@ -138,6 +138,9 @@ extern unsigned long profile_pc(struct pt_regs *regs);
#define profile_pc(regs) instruction_pointer(regs)
#endif
+long do_syscall_trace_enter(struct pt_regs *regs);
+void do_syscall_trace_leave(struct pt_regs *regs);
+
#define kernel_stack_pointer(regs) ((regs)->gpr[1])
static inline int is_syscall_success(struct pt_regs *regs)
{
diff --git a/arch/powerpc/include/asm/signal.h b/arch/powerpc/include/asm/signal.h
index 0803ca8b9149..0113be8dcb59 100644
--- a/arch/powerpc/include/asm/signal.h
+++ b/arch/powerpc/include/asm/signal.h
@@ -6,4 +6,6 @@
#include <uapi/asm/signal.h>
#include <uapi/asm/ptrace.h>
+void do_notify_resume(struct pt_regs *regs, unsigned long thread_info_flags);
+
#endif /* _ASM_POWERPC_SIGNAL_H */
diff --git a/arch/powerpc/include/asm/switch_to.h b/arch/powerpc/include/asm/switch_to.h
index 5b03d8a82409..231fcb2058cf 100644
--- a/arch/powerpc/include/asm/switch_to.h
+++ b/arch/powerpc/include/asm/switch_to.h
@@ -5,6 +5,7 @@
#ifndef _ASM_POWERPC_SWITCH_TO_H
#define _ASM_POWERPC_SWITCH_TO_H
+#include <linux/sched.h>
#include <asm/reg.h>
struct thread_struct;
@@ -22,6 +23,9 @@ extern void switch_booke_debug_regs(struct debug_reg *new_debug);
extern int emulate_altivec(struct pt_regs *);
+void restore_math(struct pt_regs *regs);
+void restore_tm_state(struct pt_regs *regs);
+
extern void flush_all_to_thread(struct task_struct *);
extern void giveup_all(struct task_struct *);
diff --git a/arch/powerpc/include/asm/time.h b/arch/powerpc/include/asm/time.h
index 54f4ec1f9fab..ba97858c9d76 100644
--- a/arch/powerpc/include/asm/time.h
+++ b/arch/powerpc/include/asm/time.h
@@ -199,5 +199,8 @@ DECLARE_PER_CPU(u64, decrementers_next_tb);
/* Convert timebase ticks to nanoseconds */
unsigned long long tb_to_ns(unsigned long long tb_ticks);
+/* SPLPAR */
+void accumulate_stolen_time(void);
+
#endif /* __KERNEL__ */
#endif /* __POWERPC_TIME_H */
diff --git a/arch/powerpc/kernel/Makefile b/arch/powerpc/kernel/Makefile
index 56dfa7a2a6f2..7f53cc07f933 100644
--- a/arch/powerpc/kernel/Makefile
+++ b/arch/powerpc/kernel/Makefile
@@ -52,7 +52,8 @@ obj-y := cputable.o ptrace.o syscalls.o \
of_platform.o prom_parse.o
obj-$(CONFIG_PPC64) += setup_64.o sys_ppc32.o \
signal_64.o ptrace32.o \
- paca.o nvram_64.o firmware.o
+ paca.o nvram_64.o firmware.o \
+ syscall_64.o
obj-$(CONFIG_VDSO32) += vdso32/
obj-$(CONFIG_PPC_WATCHDOG) += watchdog.o
obj-$(CONFIG_HAVE_HW_BREAKPOINT) += hw_breakpoint.o
diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S
index 5a3e0b5c9ad1..2ec825a85f5b 100644
--- a/arch/powerpc/kernel/entry_64.S
+++ b/arch/powerpc/kernel/entry_64.S
@@ -63,12 +63,6 @@ exception_marker:
.globl system_call_common
system_call_common:
-#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
-BEGIN_FTR_SECTION
- extrdi. r10, r12, 1, (63-MSR_TS_T_LG) /* transaction active? */
- bne .Ltabort_syscall
-END_FTR_SECTION_IFSET(CPU_FTR_TM)
-#endif
mr r10,r1
ld r1,PACAKSAVE(r13)
std r10,0(r1)
@@ -76,350 +70,118 @@ END_FTR_SECTION_IFSET(CPU_FTR_TM)
std r12,_MSR(r1)
std r0,GPR0(r1)
std r10,GPR1(r1)
+ std r2,GPR2(r1)
#ifdef CONFIG_PPC_FSL_BOOK3E
+ andi. r10,r12,MSR_PR
+ beq 1f /* if from kernel mode */
START_BTB_FLUSH_SECTION
BTB_FLUSH(r10)
END_BTB_FLUSH_SECTION
+1:
#endif
- ACCOUNT_CPU_USER_ENTRY(r13, r10, r11)
- std r2,GPR2(r1)
+ ld r2,PACATOC(r13)
+ mfcr r12
+ li r11,0
+ /* Can we avoid saving r3-r8 in common case? */
std r3,GPR3(r1)
- mfcr r2
std r4,GPR4(r1)
std r5,GPR5(r1)
std r6,GPR6(r1)
std r7,GPR7(r1)
std r8,GPR8(r1)
- li r11,0
+ /* Zero r9-r12, this should only be required when restoring all GPRs */
std r11,GPR9(r1)
std r11,GPR10(r1)
std r11,GPR11(r1)
std r11,GPR12(r1)
- std r11,_XER(r1)
- std r11,_CTR(r1)
std r9,GPR13(r1)
SAVE_NVGPRS(r1)
+ std r11,_XER(r1)
+ std r11,_CTR(r1)
mflr r10
+
/*
* This clears CR0.SO (bit 28), which is the error indication on
* return from this system call.
*/
- rldimi r2,r11,28,(63-28)
+ rldimi r12,r11,28,(63-28)
li r11,0xc00
std r10,_LINK(r1)
std r11,_TRAP(r1)
+ std r12,_CCR(r1)
std r3,ORIG_GPR3(r1)
- std r2,_CCR(r1)
- ld r2,PACATOC(r13)
- addi r9,r1,STACK_FRAME_OVERHEAD
+ addi r10,r1,STACK_FRAME_OVERHEAD
ld r11,exception_marker@toc(r2)
- std r11,-16(r9) /* "regshere" marker */
-
- kuap_check_amr r10, r11
-
-#if defined(CONFIG_VIRT_CPU_ACCOUNTING_NATIVE) && defined(CONFIG_PPC_SPLPAR)
-BEGIN_FW_FTR_SECTION
- /* see if there are any DTL entries to process */
- ld r10,PACALPPACAPTR(r13) /* get ptr to VPA */
- ld r11,PACA_DTL_RIDX(r13) /* get log read index */
- addi r10,r10,LPPACA_DTLIDX
- LDX_BE r10,0,r10 /* get log write index */
- cmpd r11,r10
- beq+ 33f
- bl accumulate_stolen_time
- REST_GPR(0,r1)
- REST_4GPRS(3,r1)
- REST_2GPRS(7,r1)
- addi r9,r1,STACK_FRAME_OVERHEAD
-33:
-END_FW_FTR_SECTION_IFSET(FW_FEATURE_SPLPAR)
-#endif /* CONFIG_VIRT_CPU_ACCOUNTING_NATIVE && CONFIG_PPC_SPLPAR */
-
- /*
- * A syscall should always be called with interrupts enabled
- * so we just unconditionally hard-enable here. When some kind
- * of irq tracing is used, we additionally check that condition
- * is correct
- */
-#if defined(CONFIG_PPC_IRQ_SOFT_MASK_DEBUG) && defined(CONFIG_BUG)
- lbz r10,PACAIRQSOFTMASK(r13)
-1: tdnei r10,IRQS_ENABLED
- EMIT_BUG_ENTRY 1b,__FILE__,__LINE__,BUGFLAG_WARNING
-#endif
-
-#ifdef CONFIG_PPC_BOOK3E
- wrteei 1
-#else
- li r11,MSR_RI
- ori r11,r11,MSR_EE
- mtmsrd r11,1
-#endif /* CONFIG_PPC_BOOK3E */
-
-system_call: /* label this so stack traces look sane */
- /* We do need to set SOFTE in the stack frame or the return
- * from interrupt will be painful
- */
- li r10,IRQS_ENABLED
- std r10,SOFTE(r1)
-
- ld r11, PACA_THREAD_INFO(r13)
- ld r10,TI_FLAGS(r11)
- andi. r11,r10,_TIF_SYSCALL_DOTRACE
- bne .Lsyscall_dotrace /* does not return */
- cmpldi 0,r0,NR_syscalls
- bge- .Lsyscall_enosys
-
-.Lsyscall:
-/*
- * Need to vector to 32 Bit or default sys_call_table here,
- * based on caller's run-mode / personality.
- */
- ld r11,SYS_CALL_TABLE@toc(2)
- andis. r10,r10,_TIF_32BIT@h
- beq 15f
- ld r11,COMPAT_SYS_CALL_TABLE@toc(2)
- clrldi r3,r3,32
- clrldi r4,r4,32
- clrldi r5,r5,32
- clrldi r6,r6,32
- clrldi r7,r7,32
- clrldi r8,r8,32
-15:
- slwi r0,r0,3
-
- barrier_nospec_asm
- /*
- * Prevent the load of the handler below (based on the user-passed
- * system call number) being speculatively executed until the test
- * against NR_syscalls and branch to .Lsyscall_enosys above has
- * committed.
- */
+ std r11,-16(r10) /* "regshere" marker */
- ldx r12,r11,r0 /* Fetch system call handler [ptr] */
- mtctr r12
- bctrl /* Call handler */
+ /* Calling convention has r9 = orig r0, r10 = regs */
+ mr r9,r0
+ bl system_call_exception
- /* syscall_exit can exit to kernel mode, via ret_from_kernel_thread */
.Lsyscall_exit:
- std r3,RESULT(r1)
-
-#ifdef CONFIG_DEBUG_RSEQ
- /* Check whether the syscall is issued inside a restartable sequence */
- addi r3,r1,STACK_FRAME_OVERHEAD
- bl rseq_syscall
- ld r3,RESULT(r1)
-#endif
-
- ld r12, PACA_THREAD_INFO(r13)
-
- ld r8,_MSR(r1)
-
-/*
- * This is a few instructions into the actual syscall exit path (which actually
- * starts at .Lsyscall_exit) to cater to kprobe blacklisting and to reduce the
- * number of visible symbols for profiling purposes.
- *
- * We can probe from system_call until this point as MSR_RI is set. But once it
- * is cleared below, we won't be able to take a trap.
- *
- * This is blacklisted from kprobes further below with _ASM_NOKPROBE_SYMBOL().
- */
-system_call_exit:
- /*
- * Disable interrupts so current_thread_info()->flags can't change,
- * and so that we don't get interrupted after loading SRR0/1.
- *
- * Leave MSR_RI enabled for now, because with THREAD_INFO_IN_TASK we
- * could fault on the load of the TI_FLAGS below.
- */
-#ifdef CONFIG_PPC_BOOK3E
- wrteei 0
-#else
- li r11,MSR_RI
- mtmsrd r11,1
-#endif /* CONFIG_PPC_BOOK3E */
+ addi r4,r1,STACK_FRAME_OVERHEAD
+ bl syscall_exit_prepare
- ld r9,TI_FLAGS(r12)
- li r11,-MAX_ERRNO
- andi. r0,r9,(_TIF_SYSCALL_DOTRACE|_TIF_SINGLESTEP|_TIF_USER_WORK_MASK|_TIF_PERSYSCALL_MASK)
- bne- .Lsyscall_exit_work
+ ld r2,_CCR(r1)
+ ld r4,_NIP(r1)
+ ld r5,_MSR(r1)
+ ld r6,_LINK(r1)
- andi. r0,r8,MSR_FP
- beq 2f
-#ifdef CONFIG_ALTIVEC
- andis. r0,r8,MSR_VEC@h
- bne 3f
-#endif
-2: addi r3,r1,STACK_FRAME_OVERHEAD
- bl restore_math
- ld r8,_MSR(r1)
- ld r3,RESULT(r1)
- li r11,-MAX_ERRNO
-
-3: cmpld r3,r11
- ld r5,_CCR(r1)
- bge- .Lsyscall_error
-.Lsyscall_error_cont:
- ld r7,_NIP(r1)
BEGIN_FTR_SECTION
stdcx. r0,0,r1 /* to clear the reservation */
END_FTR_SECTION_IFCLR(CPU_FTR_STCX_CHECKS_ADDRESS)
- andi. r6,r8,MSR_PR
- ld r4,_LINK(r1)
- kuap_check_amr r10, r11
-
-#ifdef CONFIG_PPC_BOOK3S
- /*
- * Clear MSR_RI, MSR_EE is already and remains disabled. We could do
- * this later, but testing shows that doing it here causes less slow
- * down than doing it closer to the rfid.
- */
- li r11,0
- mtmsrd r11,1
+ mtspr SPRN_SRR0,r4
+ mtspr SPRN_SRR1,r5
+#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
+ std r5,PACATMSCRATCH(r13)
#endif
+ mtlr r6
- beq- 1f
- ACCOUNT_CPU_USER_EXIT(r13, r11, r12)
+ cmpdi r3,0
+ bne syscall_restore_regs
+.Lsyscall_restore_regs_cont:
BEGIN_FTR_SECTION
HMT_MEDIUM_LOW
END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR)
-#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
- std r8, PACATMSCRATCH(r13)
-#endif
-
/*
* We don't need to restore AMR on the way back to userspace for KUAP.
* The value of AMR only matters while we're in the kernel.
*/
- ld r13,GPR13(r1) /* only restore r13 if returning to usermode */
+ mtcr r2
ld r2,GPR2(r1)
+ ld r3,GPR3(r1)
+ ld r13,GPR13(r1)
ld r1,GPR1(r1)
- mtlr r4
- mtcr r5
- mtspr SPRN_SRR0,r7
- mtspr SPRN_SRR1,r8
RFI_TO_USER
b . /* prevent speculative execution */
+_ASM_NOKPROBE_SYMBOL(system_call_common);
-1: /* exit to kernel */
- kuap_restore_amr r2
-
- ld r2,GPR2(r1)
- ld r1,GPR1(r1)
- mtlr r4
- mtcr r5
- mtspr SPRN_SRR0,r7
- mtspr SPRN_SRR1,r8
- RFI_TO_KERNEL
- b . /* prevent speculative execution */
-
-.Lsyscall_error:
- oris r5,r5,0x1000 /* Set SO bit in CR */
- neg r3,r3
- std r5,_CCR(r1)
- b .Lsyscall_error_cont
-
-/* Traced system call support */
-.Lsyscall_dotrace:
- addi r3,r1,STACK_FRAME_OVERHEAD
- bl do_syscall_trace_enter
-
- /*
- * We use the return value of do_syscall_trace_enter() as the syscall
- * number. If the syscall was rejected for any reason do_syscall_trace_enter()
- * returns an invalid syscall number and the test below against
- * NR_syscalls will fail.
- */
- mr r0,r3
-
- /* Restore argument registers just clobbered and/or possibly changed. */
- ld r3,GPR3(r1)
- ld r4,GPR4(r1)
- ld r5,GPR5(r1)
- ld r6,GPR6(r1)
- ld r7,GPR7(r1)
- ld r8,GPR8(r1)
-
- /* Repopulate r9 and r10 for the syscall path */
- addi r9,r1,STACK_FRAME_OVERHEAD
- ld r10, PACA_THREAD_INFO(r13)
- ld r10,TI_FLAGS(r10)
-
- cmpldi r0,NR_syscalls
- blt+ .Lsyscall
-
- /* Return code is already in r3 thanks to do_syscall_trace_enter() */
- b .Lsyscall_exit
-
-
-.Lsyscall_enosys:
- li r3,-ENOSYS
- b .Lsyscall_exit
-
-.Lsyscall_exit_work:
- /* If TIF_RESTOREALL is set, don't scribble on either r3 or ccr.
- If TIF_NOERROR is set, just save r3 as it is. */
-
- andi. r0,r9,_TIF_RESTOREALL
- beq+ 0f
+syscall_restore_regs:
+ ld r3,_CTR(r1)
+ ld r4,_XER(r1)
REST_NVGPRS(r1)
- b 2f
-0: cmpld r3,r11 /* r11 is -MAX_ERRNO */
- blt+ 1f
- andi. r0,r9,_TIF_NOERROR
- bne- 1f
- ld r5,_CCR(r1)
- neg r3,r3
- oris r5,r5,0x1000 /* Set SO bit in CR */
- std r5,_CCR(r1)
-1: std r3,GPR3(r1)
-2: andi. r0,r9,(_TIF_PERSYSCALL_MASK)
- beq 4f
-
- /* Clear per-syscall TIF flags if any are set. */
-
- li r11,_TIF_PERSYSCALL_MASK
- addi r12,r12,TI_FLAGS
-3: ldarx r10,0,r12
- andc r10,r10,r11
- stdcx. r10,0,r12
- bne- 3b
- subi r12,r12,TI_FLAGS
-
-4: /* Anything else left to do? */
-BEGIN_FTR_SECTION
- lis r3,DEFAULT_PPR@highest /* Set default PPR */
- sldi r3,r3,32 /* bits 11-13 are used for ppr */
- std r3,_PPR(r1)
-END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR)
-
- andi. r0,r9,(_TIF_SYSCALL_DOTRACE|_TIF_SINGLESTEP)
- beq ret_from_except_lite
-
- /* Re-enable interrupts */
-#ifdef CONFIG_PPC_BOOK3E
- wrteei 1
-#else
- li r10,MSR_RI
- ori r10,r10,MSR_EE
- mtmsrd r10,1
-#endif /* CONFIG_PPC_BOOK3E */
-
- addi r3,r1,STACK_FRAME_OVERHEAD
- bl do_syscall_trace_leave
- b ret_from_except
+ mtctr r3
+ mtspr SPRN_XER,r4
+ ld r0,GPR0(r1)
+ REST_8GPRS(4, r1)
+ ld r12,GPR12(r1)
+ b .Lsyscall_restore_regs_cont
#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
-.Ltabort_syscall:
+ .globl tabort_syscall
+tabort_syscall:
/* Firstly we need to enable TM in the kernel */
mfmsr r10
li r9, 1
rldimi r10, r9, MSR_TM_LG, 63-MSR_TM_LG
mtmsrd r10, 0
+ ld r11,_NIP(r13)
+ ld r12,_MSR(r13)
+
/* tabort, this dooms the transaction, nothing else */
li r9, (TM_CAUSE_SYSCALL|TM_CAUSE_PERSISTENT)
TABORT(R9)
@@ -438,9 +200,6 @@ END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR)
RFI_TO_USER
b . /* prevent speculative execution */
#endif
-_ASM_NOKPROBE_SYMBOL(system_call_common);
-_ASM_NOKPROBE_SYMBOL(system_call_exit);
-
_GLOBAL(ret_from_fork)
bl schedule_tail
REST_NVGPRS(r1)
diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
index 24621e7e5033..f444525da9ce 100644
--- a/arch/powerpc/kernel/process.c
+++ b/arch/powerpc/kernel/process.c
@@ -1609,7 +1609,6 @@ int copy_thread_tls(unsigned long clone_flags, unsigned long usp,
extern void ret_from_kernel_thread(void);
void (*f)(void);
unsigned long sp = (unsigned long)task_stack_page(p) + THREAD_SIZE;
- struct thread_info *ti = task_thread_info(p);
klp_init_thread_info(p);
@@ -1617,6 +1616,8 @@ int copy_thread_tls(unsigned long clone_flags, unsigned long usp,
sp -= sizeof(struct pt_regs);
childregs = (struct pt_regs *) sp;
if (unlikely(p->flags & PF_KTHREAD)) {
+ struct thread_info *ti = task_thread_info(p);
+
/* kernel thread */
memset(childregs, 0, sizeof(struct pt_regs));
childregs->gpr[1] = sp + sizeof(struct pt_regs);
@@ -1634,12 +1635,13 @@ int copy_thread_tls(unsigned long clone_flags, unsigned long usp,
} else {
/* user thread */
struct pt_regs *regs = current_pt_regs();
+
CHECK_FULL_REGS(regs);
*childregs = *regs;
if (usp)
childregs->gpr[1] = usp;
p->thread.regs = childregs;
- childregs->gpr[3] = 0; /* Result from fork() */
+ /* ret_from_fork sets fork() result to 0 */
if (clone_flags & CLONE_SETTLS) {
#ifdef CONFIG_PPC64
if (!is_32bit_task())
diff --git a/arch/powerpc/kernel/signal.h b/arch/powerpc/kernel/signal.h
index 800433685888..d396efca4068 100644
--- a/arch/powerpc/kernel/signal.h
+++ b/arch/powerpc/kernel/signal.h
@@ -10,8 +10,6 @@
#ifndef _POWERPC_ARCH_SIGNAL_H
#define _POWERPC_ARCH_SIGNAL_H
-extern void do_notify_resume(struct pt_regs *regs, unsigned long thread_info_flags);
-
extern void __user *get_sigframe(struct ksignal *ksig, unsigned long sp,
size_t frame_size, int is_32);
diff --git a/arch/powerpc/kernel/syscall_64.c b/arch/powerpc/kernel/syscall_64.c
new file mode 100644
index 000000000000..98ed970796d5
--- /dev/null
+++ b/arch/powerpc/kernel/syscall_64.c
@@ -0,0 +1,202 @@
+#include <linux/err.h>
+#include <asm/hw_irq.h>
+#include <asm/paca.h>
+#include <asm/ptrace.h>
+#include <asm/reg.h>
+#include <asm/signal.h>
+#include <asm/switch_to.h>
+#include <asm/syscall.h>
+#include <asm/time.h>
+
+extern void __noreturn tabort_syscall(void);
+
+#ifdef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
+static inline void account_cpu_user_entry(void)
+{
+ unsigned long tb = mftb();
+
+ local_paca->accounting.utime += (tb - local_paca->accounting.starttime_user);
+ local_paca->accounting.starttime = tb;
+}
+static inline void account_cpu_user_exit(void)
+{
+ unsigned long tb = mftb();
+
+ local_paca->accounting.stime += (tb - local_paca->accounting.starttime);
+ local_paca->accounting.starttime_user = tb;
+}
+#else
+static inline void account_cpu_user_entry(void)
+{
+}
+static inline void account_cpu_user_exit(void)
+{
+}
+#endif
+
+typedef long (*syscall_fn)(long, long, long, long, long, long);
+
+long system_call_exception(long r3, long r4, long r5, long r6, long r7, long r8, unsigned long r0, struct pt_regs *regs)
+{
+ unsigned long ti_flags;
+ syscall_fn f;
+
+ BUG_ON(!(regs->msr & MSR_PR));
+
+#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
+ if (unlikely(regs->msr & MSR_TS_T))
+ tabort_syscall();
+#endif
+
+ account_cpu_user_entry();
+
+#if defined(CONFIG_VIRT_CPU_ACCOUNTING_NATIVE) && defined(CONFIG_PPC_SPLPAR)
+ if (firmware_has_feature(FW_FEATURE_SPLPAR)) {
+ struct lppaca *lp = get_lppaca();
+
+ if (unlikely(local_paca->dtl_ridx != lp->dtl_idx))
+ accumulate_stolen_time();
+ }
+#endif
+
+#ifdef CONFIG_PPC_KUAP_DEBUG
+ if (mmu_has_feature(MMU_FTR_RADIX_KUAP))
+ WARN_ON_ONCE(mfspr(SPRN_AMR) != AMR_KUAP_BLOCKED);
+#endif
+
+ /*
+ * A syscall should always be called with interrupts enabled
+ * so we just unconditionally hard-enable here. When some kind
+ * of irq tracing is used, we additionally check that condition
+ * is correct
+ */
+#if defined(CONFIG_PPC_IRQ_SOFT_MASK_DEBUG)
+ WARN_ON(irq_soft_mask_return() != IRQS_ENABLED);
+ WARN_ON(local_paca->irq_happened);
+#endif
+
+ __hard_irq_enable();
+
+ /*
+ * We do need to set SOFTE in the stack frame or the return
+ * from interrupt will be painful
+ */
+ regs->softe = IRQS_ENABLED;
+
+ ti_flags = current_thread_info()->flags;
+ if (unlikely(ti_flags & _TIF_SYSCALL_DOTRACE)) {
+ /*
+ * We use the return value of do_syscall_trace_enter() as the
+ * syscall number. If the syscall was rejected for any reason
+ * do_syscall_trace_enter() returns an invalid syscall number
+ * and the test below against NR_syscalls will fail.
+ */
+ r0 = do_syscall_trace_enter(regs);
+ }
+
+ if (unlikely(r0 >= NR_syscalls))
+ return -ENOSYS;
+
+ /* May be faster to do array_index_nospec? */
+ barrier_nospec();
+
+ if (unlikely(ti_flags & _TIF_32BIT)) {
+ f = (void *)compat_sys_call_table[r0];
+
+ r3 &= 0x00000000ffffffffULL;
+ r4 &= 0x00000000ffffffffULL;
+ r5 &= 0x00000000ffffffffULL;
+ r6 &= 0x00000000ffffffffULL;
+ r7 &= 0x00000000ffffffffULL;
+ r8 &= 0x00000000ffffffffULL;
+
+ } else {
+ f = (void *)sys_call_table[r0];
+ }
+
+ return f(r3, r4, r5, r6, r7, r8);
+}
+
+unsigned long syscall_exit_prepare(unsigned long r3, struct pt_regs *regs)
+{
+ unsigned long *ti_flagsp = ¤t_thread_info()->flags;
+ unsigned long ti_flags;
+ unsigned long ret = 0;
+
+ regs->result = r3;
+
+ /* Check whether the syscall is issued inside a restartable sequence */
+ rseq_syscall(regs);
+
+ ti_flags = *ti_flagsp;
+ if (unlikely(ti_flags & _TIF_SYSCALL_DOTRACE))
+ do_syscall_trace_leave(regs);
+
+ if (unlikely(r3 >= (unsigned long)-MAX_ERRNO)) {
+ if (likely(!(ti_flags & (_TIF_NOERROR | _TIF_RESTOREALL)))) {
+ r3 = -r3;
+ regs->ccr |= 0x10000000; /* Set SO bit in CR */
+ }
+ }
+
+ if (unlikely(ti_flags & _TIF_PERSYSCALL_MASK)) {
+ if (ti_flags & _TIF_RESTOREALL)
+ ret = _TIF_RESTOREALL;
+ else
+ regs->gpr[3] = r3;
+ clear_bits(_TIF_PERSYSCALL_MASK, ti_flagsp);
+ } else {
+ regs->gpr[3] = r3;
+ }
+
+again:
+ local_irq_disable();
+ ti_flags = READ_ONCE(*ti_flagsp);
+ while (unlikely(ti_flags & _TIF_USER_WORK_MASK)) {
+ local_irq_enable();
+ if (ti_flags & _TIF_NEED_RESCHED) {
+ schedule();
+ } else {
+ /*
+ * SIGPENDING must restore signal handler function
+ * argument GPRs, and some non-volatiles (e.g., r1).
+ * Restore all for now. This could be made lighter.
+ */
+ if (ti_flags & _TIF_SIGPENDING)
+ ret |= _TIF_RESTOREALL;
+ do_notify_resume(regs, ti_flags);
+ }
+ local_irq_disable();
+ ti_flags = READ_ONCE(*ti_flagsp);
+ }
+
+#ifdef CONFIG_ALTIVEC
+ if ((regs->msr & (MSR_FP|MSR_VEC)) != (MSR_FP|MSR_VEC))
+#else
+ if ((regs->msr & MSR_FP) != MSR_FP)
+#endif
+ restore_math(regs);
+
+ /* This pattern matches prep_irq_for_idle */
+ __mtmsrd(0, 1); /* Disable MSR_EE and MSR_RI */
+ if (unlikely(lazy_irq_pending())) {
+ __mtmsrd(MSR_RI, 1);
+ local_paca->irq_happened |= PACA_IRQ_HARD_DIS;
+ local_irq_enable();
+ /* Took an interrupt which may have more exit work to do. */
+ goto again;
+ }
+ trace_hardirqs_on();
+ local_paca->irq_happened &= ~PACA_IRQ_HARD_DIS;
+ irq_soft_mask_set(IRQS_ENABLED);
+
+ account_cpu_user_exit();
+
+#ifdef CONFIG_PPC_KUAP_DEBUG
+ if (mmu_has_feature(MMU_FTR_RADIX_KUAP))
+ WARN_ON_ONCE(mfspr(SPRN_AMR) != AMR_KUAP_BLOCKED);
+#endif
+
+ return ret;
+}
+
--
2.22.0
^ permalink raw reply related
* [PATCH] ASoC: imx-audmix: register the card on a proper dev
From: Shengjiu Wang @ 2019-08-27 15:55 UTC (permalink / raw)
To: timur, nicoleotsuka, Xiubo.Lee, festevam, broonie, lgirdwood,
perex, tiwai, shawnguo, s.hauer, kernel, alsa-devel, viorel.suman
Cc: linuxppc-dev, linux-imx, linux-arm-kernel, linux-kernel
This platform device is registered from "fsl_audmix", which is
its parent device. If use pdev->dev.parent for the priv->card.dev,
the value set by dev_set_drvdata in parent device will be covered
by the value in child device.
Fixes: b86ef5367761 ("ASoC: fsl: Add Audio Mixer machine driver")
Signed-off-by: Viorel Suman <viorel.suman@nxp.com>
Signed-off-by: Shengjiu Wang <shengjiu.wang@nxp.com>
---
sound/soc/fsl/imx-audmix.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/sound/soc/fsl/imx-audmix.c b/sound/soc/fsl/imx-audmix.c
index 9e1cb18859ce..71590ca6394b 100644
--- a/sound/soc/fsl/imx-audmix.c
+++ b/sound/soc/fsl/imx-audmix.c
@@ -325,14 +325,14 @@ static int imx_audmix_probe(struct platform_device *pdev)
priv->card.num_configs = priv->num_dai_conf;
priv->card.dapm_routes = priv->dapm_routes;
priv->card.num_dapm_routes = priv->num_dapm_routes;
- priv->card.dev = pdev->dev.parent;
+ priv->card.dev = &pdev->dev;
priv->card.owner = THIS_MODULE;
priv->card.name = "imx-audmix";
platform_set_drvdata(pdev, &priv->card);
snd_soc_card_set_drvdata(&priv->card, priv);
- ret = devm_snd_soc_register_card(pdev->dev.parent, &priv->card);
+ ret = devm_snd_soc_register_card(&pdev->dev, &priv->card);
if (ret) {
dev_err(&pdev->dev, "snd_soc_register_card failed\n");
return ret;
--
2.21.0
^ permalink raw reply related
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