Commit c311c79799 ("cpumask: make "nr_cpumask_bits" unsigned")
modified mipspmu_event_init() to cast the struct perf_event cpu field to
an unsigned integer before it is compared with nr_cpumask_bits (and
*ahem* did so without copying the linux-mips mailing list or any MIPS
developers...). This is broken because the cpu field may be -1 for
events which follow a process rather than being affine to a particular
CPU. When this is the case the cast to an unsigned int results in a
value equal to ULONG_MAX, which is always greater than nr_cpumask_bits
so we always fail mipspmu_event_init() and return -ENODEV.
The check against nr_cpumask_bits seems nonsensical anyway, so this
patch simply removes it. The cpu field is going to either be -1 or a
valid CPU number. Comparing it with nr_cpumask_bits is effectively
checking that it's a valid cpu number, but it seems safe to rely on the
core perf events code to ensure that's the case.
The end result is that this fixes use of perf on MIPS when not
constraining events to a particular CPU, and fixes the "perf list hw"
command which fails to list any events without this.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Fixes: c311c79799 ("cpumask: make "nr_cpumask_bits" unsigned")
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: linux-mips@linux-mips.org
Cc: stable <stable@vger.kernel.org> # v4.12+
Patchwork: https://patchwork.linux-mips.org/patch/17323/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Pull MIPS updates from Ralf Baechle:
"This is the main pull request for 4.14 for MIPS; below a summary of
the non-merge commits:
CM:
- Rename mips_cm_base to mips_gcr_base
- Specify register size when generating accessors
- Use BIT/GENMASK for register fields, order & drop shifts
- Add cluster & block args to mips_cm_lock_other()
CPC:
- Use common CPS accessor generation macros
- Use BIT/GENMASK for register fields, order & drop shifts
- Introduce register modify (set/clear/change) accessors
- Use change_*, set_* & clear_* where appropriate
- Add CM/CPC 3.5 register definitions
- Use GlobalNumber macros rather than magic numbers
- Have asm/mips-cps.h include CM & CPC headers
- Cluster support for topology functions
- Detect CPUs in secondary clusters
CPS:
- Read GIC_VL_IDENT directly, not via irqchip driver
DMA:
- Consolidate coherent and non-coherent dma_alloc code
- Don't use dma_cache_sync to implement fd_cacheflush
FPU emulation / FP assist code:
- Another series of 14 commits fixing corner cases such as NaN
propgagation and other special input values.
- Zero bits 32-63 of the result for a CLASS.D instruction.
- Enhanced statics via debugfs
- Do not use bools for arithmetic. GCC 7.1 moans about this.
- Correct user fault_addr type
Generic MIPS:
- Enhancement of stack backtraces
- Cleanup from non-existing options
- Handle non word sized instructions when examining frame
- Fix detection and decoding of ADDIUSP instruction
- Fix decoding of SWSP16 instruction
- Refactor handling of stack pointer in get_frame_info
- Remove unreachable code from force_fcr31_sig()
- Convert to using %pOF instead of full_name
- Remove the R6000 support.
- Move FP code from *_switch.S to *_fpu.S
- Remove unused ST_OFF from r2300_switch.S
- Allow platform to specify multiple its.S files
- Add #includes to various files to ensure code builds reliable and
without warning..
- Remove __invalidate_kernel_vmap_range
- Remove plat_timer_setup
- Declare various variables & functions static
- Abstract CPU core & VP(E) ID access through accessor functions
- Store core & VP IDs in GlobalNumber-style variable
- Unify checks for sibling CPUs
- Add CPU cluster number accessors
- Prevent direct use of generic_defconfig
- Make CONFIG_MIPS_MT_SMP default y
- Add __ioread64_copy
- Remove unnecessary inclusions of linux/irqchip/mips-gic.h
GIC:
- Introduce asm/mips-gic.h with accessor functions
- Use new GIC accessor functions in mips-gic-timer
- Remove counter access functions from irq-mips-gic.c
- Remove gic_read_local_vp_id() from irq-mips-gic.c
- Simplify shared interrupt pending/mask reads in irq-mips-gic.c
- Simplify gic_local_irq_domain_map() in irq-mips-gic.c
- Drop gic_(re)set_mask() functions in irq-mips-gic.c
- Remove gic_set_polarity(), gic_set_trigger(), gic_set_dual_edge(),
gic_map_to_pin() and gic_map_to_vpe() from irq-mips-gic.c.
- Convert remaining shared reg access, local int mask access and
remaining local reg access to new accessors
- Move GIC_LOCAL_INT_* to asm/mips-gic.h
- Remove GIC_CPU_INT* macros from irq-mips-gic.c
- Move various definitions to the driver
- Remove gic_get_usm_range()
- Remove __gic_irq_dispatch() forward declaration
- Remove gic_init()
- Use mips_gic_present() in place of gic_present and remove
gic_present
- Move gic_get_c0_*_int() to asm/mips-gic.h
- Remove linux/irqchip/mips-gic.h
- Inline __gic_init()
- Inline gic_basic_init()
- Make pcpu_masks a per-cpu variable
- Use pcpu_masks to avoid reading GIC_SH_MASK*
- Clean up mti, reserved-cpu-vectors handling
- Use cpumask_first_and() in gic_set_affinity()
- Let the core set struct irq_common_data affinity
microMIPS:
- Fix microMIPS stack unwinding on big endian systems
MIPS-GIC:
- SYNC after enabling GIC region
NUMA:
- Remove the unused parent_node() macro
R6:
- Constify r2_decoder_tables
- Add accessor & bit definitions for GlobalNumber
SMP:
- Constify smp ops
- Allow boot_secondary SMP op to return errors
VDSO:
- Drop gic_get_usm_range() usage
- Avoid use of linux/irqchip/mips-gic.h
Platform changes:
Alchemy:
- Add devboard machine type to cpuinfo
- update cpu feature overrides
- Threaded carddetect irqs for devboards
AR7:
- allow NULL clock for clk_get_rate
BCM63xx:
- Fix ENETDMA_6345_MAXBURST_REG offset
- Allow NULL clock for clk_get_rate
CI20:
- Enable GPIO and RTC drivers in defconfig
- Add ethernet and fixed-regulator nodes to DTS
Generic platform:
- Move Boston and NI 169445 FIT image source to their own files
- Include asm/bootinfo.h for plat_fdt_relocated()
- Include asm/time.h for get_c0_*_int()
- Include asm/bootinfo.h for plat_fdt_relocated()
- Include asm/time.h for get_c0_*_int()
- Allow filtering enabled boards by requirements
- Don't explicitly disable CONFIG_USB_SUPPORT
- Bump default NR_CPUS to 16
JZ4700:
- Probe the jz4740-rtc driver from devicetree
Lantiq:
- Drop check of boot select from the spi-falcon driver.
- Drop check of boot select from the lantiq-flash MTD driver.
- Access boot cause register in the watchdog driver through regmap
- Add device tree binding documentation for the watchdog driver
- Add docs for the RCU DT bindings.
- Convert the fpi bus driver to a platform_driver
- Remove ltq_reset_cause() and ltq_boot_select(
- Switch to a proper reset driver
- Switch to a new drivers/soc GPHY driver
- Add an USB PHY driver for the Lantiq SoCs using the RCU module
- Use of_platform_default_populate instead of __dt_register_buses
- Enable MFD_SYSCON to be able to use it for the RCU MFD
- Replace ltq_boot_select() with dummy implementation.
Loongson 2F:
- Allow NULL clock for clk_get_rate
Malta:
- Use new GIC accessor functions
NI 169445:
- Add support for NI 169445 board.
- Only include in 32r2el kernels
Octeon:
- Add support for watchdog of 78XX SOCs.
- Add support for watchdog of CN68XX SOCs.
- Expose support for mips32r1, mips32r2 and mips64r1
- Enable more drivers in config file
- Add support for accessing the boot vector.
- Remove old boot vector code from watchdog driver
- Define watchdog registers for 70xx, 73xx, 78xx, F75xx.
- Make CSR functions node aware.
- Allow access to CIU3 IRQ domains.
- Misc cleanups in the watchdog driver
Omega2+:
- New board, add support and defconfig
Pistachio:
- Enable Root FS on NFS in defconfig
Ralink:
- Add Mediatek MT7628A SoC
- Allow NULL clock for clk_get_rate
- Explicitly request exclusive reset control in the pci-mt7620 PCI driver.
SEAD3:
- Only include in 32 bit kernels by default
VoCore:
- Add VoCore as a vendor t0 dt-bindings
- Add defconfig file"
* '4.14-features' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: (167 commits)
MIPS: Refactor handling of stack pointer in get_frame_info
MIPS: Stacktrace: Fix microMIPS stack unwinding on big endian systems
MIPS: microMIPS: Fix decoding of swsp16 instruction
MIPS: microMIPS: Fix decoding of addiusp instruction
MIPS: microMIPS: Fix detection of addiusp instruction
MIPS: Handle non word sized instructions when examining frame
MIPS: ralink: allow NULL clock for clk_get_rate
MIPS: Loongson 2F: allow NULL clock for clk_get_rate
MIPS: BCM63XX: allow NULL clock for clk_get_rate
MIPS: AR7: allow NULL clock for clk_get_rate
MIPS: BCM63XX: fix ENETDMA_6345_MAXBURST_REG offset
mips: Save all registers when saving the frame
MIPS: Add DWARF unwinding to assembly
MIPS: Make SAVE_SOME more standard
MIPS: Fix issues in backtraces
MIPS: jz4780: DTS: Probe the jz4740-rtc driver from devicetree
MIPS: Ci20: Enable RTC driver
watchdog: octeon-wdt: Add support for 78XX SOCs.
watchdog: octeon-wdt: Add support for cn68XX SOCs.
watchdog: octeon-wdt: File cleaning.
...
Pull more set_fs removal from Al Viro:
"Christoph's 'use kernel_read and friends rather than open-coding
set_fs()' series"
* 'work.set_fs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
fs: unexport vfs_readv and vfs_writev
fs: unexport vfs_read and vfs_write
fs: unexport __vfs_read/__vfs_write
lustre: switch to kernel_write
gadget/f_mass_storage: stop messing with the address limit
mconsole: switch to kernel_read
btrfs: switch write_buf to kernel_write
net/9p: switch p9_fd_read to kernel_write
mm/nommu: switch do_mmap_private to kernel_read
serial2002: switch serial2002_tty_write to kernel_{read/write}
fs: make the buf argument to __kernel_write a void pointer
fs: fix kernel_write prototype
fs: fix kernel_read prototype
fs: move kernel_read to fs/read_write.c
fs: move kernel_write to fs/read_write.c
autofs4: switch autofs4_write to __kernel_write
ashmem: switch to ->read_iter
Pull namespace updates from Eric Biederman:
"Life has been busy and I have not gotten half as much done this round
as I would have liked. I delayed it so that a minor conflict
resolution with the mips tree could spend a little time in linux-next
before I sent this pull request.
This includes two long delayed user namespace changes from Kirill
Tkhai. It also includes a very useful change from Serge Hallyn that
allows the security capability attribute to be used inside of user
namespaces. The practical effect of this is people can now untar
tarballs and install rpms in user namespaces. It had been suggested to
generalize this and encode some of the namespace information
information in the xattr name. Upon close inspection that makes the
things that should be hard easy and the things that should be easy
more expensive.
Then there is my bugfix/cleanup for signal injection that removes the
magic encoding of the siginfo union member from the kernel internal
si_code. The mips folks reported the case where I had used FPE_FIXME
me is impossible so I have remove FPE_FIXME from mips, while at the
same time including a return statement in that case to keep gcc from
complaining about unitialized variables.
I almost finished the work to get make copy_siginfo_to_user a trivial
copy to user. The code is available at:
git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace.git neuter-copy_siginfo_to_user-v3
But I did not have time/energy to get the code posted and reviewed
before the merge window opened.
I was able to see that the security excuse for just copying fields
that we know are initialized doesn't work in practice there are buggy
initializations that don't initialize the proper fields in siginfo. So
we still sometimes copy unitialized data to userspace"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
Introduce v3 namespaced file capabilities
mips/signal: In force_fcr31_sig return in the impossible case
signal: Remove kernel interal si_code magic
fcntl: Don't use ambiguous SIG_POLL si_codes
prctl: Allow local CAP_SYS_ADMIN changing exe_file
security: Use user_namespace::level to avoid redundant iterations in cap_capable()
userns,pidns: Verify the userns for new pid namespaces
signal/testing: Don't look for __SI_FAULT in userspace
signal/mips: Document a conflict with SI_USER with SIGFPE
signal/sparc: Document a conflict with SI_USER with SIGFPE
signal/ia64: Document a conflict with SI_USER with SIGFPE
signal/alpha: Document a conflict with SI_USER for SIGTRAP
Commit 34c2f668d0 ("MIPS: microMIPS: Add unaligned access support.")
added handling of microMIPS instructions to manipulate the stack
pointer. The code that was added violates code style rules with long
lines caused by lots of nested conditionals.
The added code interprets (inline) any known stack pointer manipulation
instruction to find the stack frame size. Handling the microMIPS cases
added quite a bit of complication to this function.
Refactor is_sp_move_ins to perform the interpretation of the immediate
as the instruction manipulating the stack pointer is found. This reduces
the amount of indentation required in get_frame_info, and more closely
matches the operation of is_ra_save_ins.
Suggested-by: Maciej W. Rozycki <macro@imgtec.com>
Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: Marcin Nowakowski <marcin.nowakowski@imgtec.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/16958/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The stack unwinding code uses the mips_instuction union to decode the
instructions it finds. That union uses the __BITFIELD_FIELD macro to
reorder depending on endianness. The stack unwinding code always places
16bit instructions in halfword 1 of the union. This makes the union
accesses correct for little endian systems. Similarly, 32bit
instructions are reordered such that they are correct for little endian
systems. This handling leaves unwinding the stack on big endian systems
broken, as the mips_instruction union will then look for the fields in
the wrong halfword.
To fix this, use a logical shift to place the 16bit instruction into the
correct position in the word field of the union. Use the same shifting
to order the 2 halfwords of 32bit instuctions. Then replace accesses to
the halfword with accesses to the shifted word.
In the case of the ADDIUS5 instruction, switch to using the
mm16_r5_format union member to avoid the need for a 16bit shift.
Fixes: 34c2f668d0 ("MIPS: microMIPS: Add unaligned access support.")
Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com>
Reviewed-by: James Hogan <james.hogan@imgtec.com>
Cc: Marcin Nowakowski <marcin.nowakowski@imgtec.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/16956/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
When the immediate encoded in the instruction is accessed, it is sign
extended due to being a signed value being assigned to a signed integer.
The ISA specifies that this operation is an unsigned operation.
The sign extension leads us to incorrectly decode:
801e9c8e: cbf1 sw ra,68(sp)
As having an immediate of 1073741809.
Since the instruction format does not specify signed/unsigned, and this
is currently the only location to use this instuction format, change it
to an unsigned immediate.
Fixes: bb9bc4689b ("MIPS: Calculate microMIPS ra properly when unwinding the stack")
Suggested-by: Paul Burton <paul.burton@imgtec.com>
Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com>
Reviewed-by: James Hogan <james.hogan@imgtec.com>
Cc: Marcin Nowakowski <marcin.nowakowski@imgtec.com>
Cc: Miodrag Dinic <miodrag.dinic@imgtec.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: David Daney <david.daney@cavium.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/16957/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Commit 34c2f668d0 ("MIPS: microMIPS: Add unaligned access support.")
added handling of microMIPS instructions to manipulate the stack
pointer. Unfortunately the decoding of the addiusp instruction was
incorrect, and performed a left shift by 2 bits to the raw immediate,
rather than decoding the immediate and then performing the shift, as
documented in the ISA.
This led to incomplete stack traces, due to incorrect frame sizes being
calculated. For example the instruction:
801faee0 <do_sys_poll>:
801faee0: 4e25 addiu sp,sp,-952
As decoded by objdump, would be interpreted by the existing code as
having manipulated the stack pointer by +1096.
Fix this by changing the order of decoding the immediate and applying
the left shift. Also change to accessing the instuction through the
union to avoid the endianness problem of accesing halfword[0], which
will fail on big endian systems.
Cope with the special behaviour of immediates 0x0, 0x1, 0x1fe and 0x1ff
by XORing with 0x100 again if mod(immediate) < 4. This logic was tested
with the following test code:
int main(int argc, char **argv)
{
unsigned int enc;
int imm;
for (enc = 0; enc < 512; ++enc) {
int tmp = enc << 2;
imm = -(signed short)(tmp | ((tmp & 0x100) ? 0xfe00 : 0));
unsigned short tmp = enc;
tmp = (tmp ^ 0x100) - 0x100;
if ((unsigned short)(tmp + 2) < 4)
tmp ^= 0x100;
imm = -(signed short)(tmp << 2);
printf("%#x\t%d\t->\t(%#x\t%d)\t%#x\t%d\n",
enc, enc,
(short)tmp, (short)tmp,
imm, imm);
}
return EXIT_SUCCESS;
}
Which generates the table:
input encoding -> tmp (matching manual) frame size
-----------------------------------------------------------------------
0 0 -> (0x100 256) 0xfffffc00 -1024
0x1 1 -> (0x101 257) 0xfffffbfc -1028
0x2 2 -> (0x2 2) 0xfffffff8 -8
0x3 3 -> (0x3 3) 0xfffffff4 -12
...
0xfe 254 -> (0xfe 254) 0xfffffc08 -1016
0xff 255 -> (0xff 255) 0xfffffc04 -1020
0x100 256 -> (0xffffff00 -256) 0x400 1024
0x101 257 -> (0xffffff01 -255) 0x3fc 1020
...
0x1fc 508 -> (0xfffffffc -4) 0x10 16
0x1fd 509 -> (0xfffffffd -3) 0xc 12
0x1fe 510 -> (0xfffffefe -258) 0x408 1032
0x1ff 511 -> (0xfffffeff -257) 0x404 1028
Thanks to James Hogan for the test code & verifying the logic.
Fixes: 34c2f668d0 ("MIPS: microMIPS: Add unaligned access support.")
Suggested-by: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: Marcin Nowakowski <marcin.nowakowski@imgtec.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/16955/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The addiusp instruction uses the pool16d opcode, with bit 0 of the
immediate set. The test for the addiusp opcode erroneously did a logical
and of the immediate with mm_addiusp_func, which has value 1, so this
test always passes when the immediate is non-zero.
Fix the test by replacing the logical and with a bitwise and.
Fixes: 34c2f668d0 ("MIPS: microMIPS: Add unaligned access support.")
Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: Marcin Nowakowski <marcin.nowakowski@imgtec.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/16954/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Commit 34c2f668d0 ("MIPS: microMIPS: Add unaligned access support.")
added fairly broken support for handling 16bit microMIPS instructions in
get_frame_info(). It adjusts the instruction pointer by 16bits in the
case of a 16bit sp move instruction, but not any other 16bit
instruction.
Commit b6c7a324df ("MIPS: Fix get_frame_info() handling of microMIPS
function size") goes some way to fixing get_frame_info() to iterate over
microMIPS instuctions, but the instruction pointer is still manipulated
using a postincrement, and is of union mips_instruction type. Since the
union is sized to the largest member (a word), but microMIPS
instructions are a mix of halfword and word sizes, the function does not
always iterate correctly, ending up misaligned with the instruction
stream and interpreting it incorrectly.
Since the instruction modifying the stack pointer is usually the first
in the function, that one is usually handled correctly. But the
instruction which saves the return address to the sp is some variable
number of instructions into the frame and is frequently missed due to
not being on a word boundary, leading to incomplete walking of the
stack.
Fix this by incrementing the instruction pointer based on the size of
the previously decoded instruction (& remove the hack introduced by
commit 34c2f668d0 ("MIPS: microMIPS: Add unaligned access support.")
which adjusts the instruction pointer in the case of a 16bit sp move
instruction, but not any other).
Fixes: 34c2f668d0 ("MIPS: microMIPS: Add unaligned access support.")
Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: Marcin Nowakowski <marcin.nowakowski@imgtec.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/16953/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
I saw two problems when doing backtraces:
The compiler was putting a "fast return" at the top of some
functions, before it set up the frame. The backtrace code
would stop when it saw a jump instruction, so it would never
get to the stack frame setup and would thus misinterpret it.
To fix this, don't look for jump instructions until the
frame setup has been seen.
The assembly code here is:
ffffffff80b885a0 <serial8250_handle_irq>:
ffffffff80b885a0: c8a00003 bbit0 a1,0x0,ffffffff80b885b0 <serial8250_handle_irq+0x10>
ffffffff80b885a4: 0000102d move v0,zero
ffffffff80b885a8: 03e00008 jr ra
ffffffff80b885ac: 00000000 nop
ffffffff80b885b0: 67bdffd0 daddiu sp,sp,-48
ffffffff80b885b4: ffb00008 sd s0,8(sp)
The second problem was the compiler was putting the last
instruction of the frame save in the delay slot of the
jump instruction. If it saved the RA in there, the
backtrace could would miss it and misinterpret the frame.
To fix this, make sure to process the instruction after
the first jump seen.
The assembly code for this is:
ffffffff80806fd0 <plat_irq_dispatch>:
ffffffff80806fd0: 67bdffd0 daddiu sp,sp,-48
ffffffff80806fd4: ffb30020 sd s3,32(sp)
ffffffff80806fd8: 24130018 li s3,24
ffffffff80806fdc: ffb20018 sd s2,24(sp)
ffffffff80806fe0: 3c12811c lui s2,0x811c
ffffffff80806fe4: ffb10010 sd s1,16(sp)
ffffffff80806fe8: 3c11811c lui s1,0x811c
ffffffff80806fec: ffb00008 sd s0,8(sp)
ffffffff80806ff0: 3c10811c lui s0,0x811c
ffffffff80806ff4: 08201c03 j ffffffff8080700c <plat_irq_dispa
tch+0x3c>
ffffffff80806ff8: ffbf0028 sd ra,40(sp)
Signed-off-by: Corey Minyard <cminyard@mvista.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/16992/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Use proper ssize_t and size_t types for the return value and count
argument, move the offset last and make it an in/out argument like
all other read/write helpers, and make the buf argument a void pointer
to get rid of lots of casts in the callers.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
linux/irqchip/mips-gic.h is included in a few files that don't actually
use it at all. Remove these unnecessary inclusions in preparation for
removing the header.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17048/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
In preparation for removing the gic_present global variable, switch to
using the mips_gic_present() function instead. For the most part this is
a straightforward substitution. In cases which previously wrapped the
GIC case in an #ifdef CONFIG_MIPS_GIC that #ifdef has been removed,
since mips_gic_present() will return a compile-time constant false
allowing the affected code to be optimised out anyway.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17044/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
We don't really need gic_get_usm_range() to abstract discovery of the
address of the GIC user-visible section now that we have access to its
base address globally.
Switch to calculating it ourselves, which will allow us to stop
requiring the irqchip driver to care about a counter exposed to userland
for use via the VDSO.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17040/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Rather than calling the gic_read_local_vp_id() function from the GIC
irqchip driver, call read_gic_vl_ident() to read the GIC_VL_IDENT
register directly. This will allow us to remove gic_read_local_vp_id()
from the irqchip driver in a further patch, since that driver doesn't
actually care about the register's value.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17023/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
As a first step towards supporting multi-cluster systems, detect cores &
VPs in secondary clusters & record their cluster information in the
cpu_data array. The "VP topology" line printed during boot is extended
to display multiple clusters. On a single cluster it shows output like
the following:
VP topology: {4,4}
This would indicate a system with 2 cores which each contain 4 VPs. We
extend this to cover multiple clusters in a natural way:
VP topology: {4,4},{2,2}
This would indicate a system with 2 clusters. The first cluster contains
2 cores which each contain 4 VPs. The second cluster contains 2 cores
which each contain 2 VPs.
Actually booting these cores & VPs is left to further patches once other
pieces are in place.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17017/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Modify the functions we use to read information about the topology of
the system (the number of cores, VPs & IOCUs that it contains) in order
to take into account multiple clusters, and provide a new function to
determine the number of clusters in the system.
Users of these functions are modified only such that they continue to
build successfully - having them actually handle multiple clusters is
left to further patches.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17016/
Patchwork: https://patchwork.linux-mips.org/patch/17218/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
With Coherence Manager (CM) 3.5 information about the topology of the
system, which has previously only been available through & accessed from
the CM, is now also provided by the Cluster Power Controller (CPC). This
includes a new CPC_CONFIG register mirroring GCR_CONFIG, and similarly a
new CPC_Cx_CONFIG register mirroring GCR_Cx_CONFIG.
In preparation for adjusting functions such as mips_cm_numcores(), which
have previously only needed to access the CM, to also access the CPC
this patch modifies the way we use the various CPS headers. Rather than
having users include asm/mips-cm.h or asm/mips-cpc.h individually we
instead have users include asm/mips-cps.h which in turn includes
asm/mips-cm.h & asm/mips-cpc.h. This means that users will gain access
to both CM & CPC registers by including one header, and most importantly
it makes asm/mips-cps.h an ideal location for helper functions which
need to access the various components of the CPS.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17015/
Patchwork: https://patchwork.linux-mips.org/patch/17217/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Allow the boot_secondary SMP op to return an error to __cpu_up(), which
will in turn return it to its caller.
This will allow SMP implementations to return errors quickly in cases
they they know have failed, rather than relying upon __cpu_up()
eventually timing out waiting for the cpu_running completion.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17014/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
With CM >= 3.5 we have the notion of multiple clusters & can access
their CM, CPC & GIC registers via the apporpriate redirect/other
register blocks. In order to allow for this introduce cluster & block
arguments to mips_cm_lock_other() which configures the redirect/other
region to point at the appropriate cluster, core, VP & register block.
Since we now have 4 arguments to mips_cm_lock_other() & a common use is
likely to be to target the cluster, core & VP corresponding to a
particular Linux CPU number we also add a new mips_cm_lock_other_cpu()
helper function which handles that without the caller needing to
manually pull out the cluster, core & VP numbers.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17013/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Introduce cpu_cluster() & cpu_set_cluster() accessor functions in the
same vein as cpu_core(), cpu_vpe_id() & their set variants. These will
be used in further patches to allow users to get or set a CPUs cluster
number.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17012/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Up until now we have open-coded checks for whether CPUs are siblings,
with slight variations on whether we consider the package ID or not.
This will only get more complex when we introduce cluster support, so in
preparation for that this patch introduces a cpus_are_siblings()
function which can be used to check whether or not 2 CPUs are siblings
in a consistent manner.
By checking globalnumber with the VP ID masked out this also has the
neat side effect of being ready for multi-cluster systems already.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Acked-by: Rafael J. Wysocki <rjw@rjwysocki.net>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17011/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This patch modifies the way we store core & VP IDs such that we store
them in a single 32 bit integer whose format matches that of the MIPSr6
GlobalNumber register. Whereas we have previously stored core & VP IDs
in separate fields, storing them in a single GlobalNumber-like field:
1) Reduces the size of struct cpuinfo_mips by 4 bytes, and will allow
it to not grow when cluster support is added.
2) Gives us a natural place to store cluster number, which matches up
with what the architecture provides.
3) Will be useful in the future as a parameter to the MIPSr6 GINVI
instruction to specify a target CPU whose icache that instruction
should operate on.
The cpu_set*() accessor functions are moved out of the asm/cpu-info.h
header in order to allow them to use the WARN_ON macro, which is
unusable in asm/cpu-info.h due to include ordering.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17010/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
We currently have fields in struct cpuinfo_mips for the core & VP(E) ID
of a particular CPU, and various pieces of code directly access those
fields. This patch abstracts such access by introducing accessor
functions cpu_core(), cpu_set_core(), cpu_vpe_id() & cpu_set_vpe_id()
and having code that needs to access these values call those functions
rather than directly accessing the struct cpuinfo_mips fields. This
prepares us for changes to the way in which those values are stored in
later patches.
The cpu_vpe_id() function is introduced even though we already had a
cpu_vpe_id() macro for a couple of reasons:
1) It's more consistent with the core, and future cluster, accessors.
2) It ensures a sensible return type without explicit casts.
3) It's generally preferable to use functions rather than macros.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17009/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
We now have definitions for the GlobalNumber register in asm/mipsregs.h,
so use them in place of magic numbers in cps-vec.S.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17008/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Make use of the new change_*, set_* & clear_* accessor functions for CPS
(CM, CPC & GIC) registers where doing so makes the code easier to read
or shortens it without adversely affecting readability.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17005/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Tidy up asm/mips-cpc.h in a similar way to what "MIPS: CM: Use
BIT/GENMASK for register fields, order & drop shifts" did for
asm/mips-cm.h.
We use BIT() & GENMASK() to simplify the definition of register fields,
drop the _SHF definitions since that information can be found in the
_MSK ones, and then drop the _MSK suffix.
Fields definitions are moved to be next to the appropriate register
definition, making it easier to link the two & keep everything ordered
by register address. Comments are added including the name of each
register & a brief description of its purpose which helps to understand
what registers are for, link them back to hardware documentation or grep
for them.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17003/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
If a restartable syscall is called using the indirect o32 syscall
handler - eg: syscall(__NR_waitid, ...), then it is possible for the
incorrect arguments to be passed to the syscall after it has been
restarted. This is because the syscall handler tries to shift all the
registers down one place in pt_regs so that when the syscall is restarted,
the "real" syscall is called instead. Unfortunately it only shifts the
arguments passed in registers, not the arguments on the user stack. This
causes the 4th argument to be duplicated when the syscall is restarted.
Fix by removing all the pt_regs shifting so that the indirect syscall
handler is called again when the syscall is restarted. The comment "some
syscalls like execve get their arguments from struct pt_regs" is long
out of date so this should now be safe.
Signed-off-by: James Cowgill <James.Cowgill@imgtec.com>
Reviewed-by: James Hogan <james.hogan@imgtec.com>
Tested-by: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/15856/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Since commit 669c409222 ("MIPS: Give __secure_computing() access to
syscall arguments."), upon syscall entry when seccomp is enabled,
syscall_trace_enter() passes a carefully prepared struct seccomp_data
containing syscall arguments to __secure_computing(). Unfortunately it
directly uses mips_get_syscall_arg() and fails to take into account the
indirect O32 system calls (i.e. syscall(2)) which put the system call
number in a0 and have the arguments shifted up by one entry.
We can't just revert that commit as samples/bpf/tracex5 would break
again, so use syscall_get_arguments() which already takes indirect
syscalls into account instead of directly using mips_get_syscall_arg(),
similar to what populate_seccomp_data() does.
This also removes the redundant error checking of the
mips_get_syscall_arg() return value (get_user() already zeroes the
result if an argument from the stack can't be loaded).
Reported-by: James Cowgill <James.Cowgill@imgtec.com>
Fixes: 669c409222 ("MIPS: Give __secure_computing() access to syscall arguments.")
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: David Daney <david.daney@cavium.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Will Drewry <wad@chromium.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: netdev@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16994/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
There's no reason for us not to use BIT() & GENMASK() in asm/mips-cm.h
when declaring macros corresponding to register fields. This patch
modifies our definitions to do so.
The *_SHF definitions are removed entirely - they duplicate information
found in the masks, are infrequently used & can be replaced with use of
__ffs() where needed.
The *_MSK definitions then lose their _MSK suffix which is now somewhat
redundant, and users are modified to match.
The field definitions are moved to follow the appropriate register's
accessor functions, which helps to keep the field definitions in order &
to find the appropriate fields for a given register. Whilst here a
comment is added describing each register & including its name, which is
helpful both for linking the register back to hardware documentation &
for grepping purposes.
This also cleans up a couple of issues that became obvious as a result
of making the changes described above:
- We previously had definitions for GCR_Cx_RESET_EXT_BASE & a phony
copy of that named GCR_RESET_EXT_BASE - a register which does not
exist. The bad definitions were added by commit 497e803ebf ("MIPS:
smp-cps: Ensure secondary cores start with EVA disabled") and made
use of from boot_core(), which is now modified to use the
GCR_Cx_RESET_EXT_BASE definitions.
- We had a typo in CM_GCR_ERROR_CAUSE_ERRINGO_MSK - we now correctly
define this as inFo rather than inGo.
Now that we don't duplicate field information between _SHF & _MSK
definitions, and keep the fields next to the register accessors, it will
be much easier to spot & prevent any similar oddities being introduced
in the future.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17001/
Patchwork: https://patchwork.linux-mips.org/patch/17216/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Some CM registers are always 32 bits, or at least only use bits in the
lower 32 bits of the register. For these registers it is wasteful for us
to generate accessors which bother to check mips_cm_is64 & perform 64
bit accesses.
This patch modifies the accessor generation to take into account the
size of the register, and for 32 bit registers we generate accessors
which only ever perform 32 bit accesses. For 64 bit registers we either
perform a 64 bit access or two 32 bit accesses, depending upon the value
of mips_cm_is64. Doing this saves us ~1.5KiB of code in a generic 64r6el
kernel, and perhaps more importantly simplifies various code paths.
This removes the read64_gcr_* accessors, so mips_cm_error_report() is
modified to stop using them & instead use the regular read_gcr_*
accessors which will return 64 bit values from the 64 bit registers.
The new accessor macros are placed in asm/mips-cps.h such that they can
be shared by CPC & GIC code in later patches.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17000/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
We currently have a mips_cm_base variable which holds the base address
of the Coherence Manager (CM) Global Configuration Registers (GCRs), and
accessor functions which use the GCR in their names. This works fine,
but gets in the way of sharing the code to generate the accessor
functions with other blocks (ie. CPC & GIC) because that code would then
need to separately handle the name of the base address variable & the
name used in the accessor functions.
In order to prepare for sharing the accessor generation code between CM,
CPC & GIC code this patch renames mips_cm_base to mips_gcr_base such
that the "gcr" portion is common to both the base address variable & the
accessor function names.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16999/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
We currently have various variables & functions which are only used
within a single translation unit, but which we don't declare static.
This causes various sparse warnings of the form:
arch/mips/kernel/mips-r2-to-r6-emul.c:49:1: warning: symbol
'mipsr2emustats' was not declared. Should it be static?
arch/mips/kernel/unaligned.c:1381:11: warning: symbol 'reg16to32st'
was not declared. Should it be static?
arch/mips/mm/mmap.c:146:15: warning: symbol 'arch_mmap_rnd' was not
declared. Should it be static?
Fix these & others by declaring various affected variables & functions
static, avoiding the sparse warnings & redundant symbols.
[ralf@linux-mips.org: Add Marcin's build fix.]
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: trivial@kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/17176/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The plat_timer_setup() function is entirely unused - nothing calls it,
and no platforms provide it. Perhaps our dummy implementation was once
useful as an aid in forward porting platforms, but its time has long
since passed so let's remove the dead code.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: trivial@kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/17175/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
arch/mips/kernel/idle.c provides our implementation of the
arch_cpu_idle() function, but doesn't include the linux/cpu.h header
which declares it. This leads to a warning from sparse:
arch/mips/kernel/idle.c:256:6: warning: symbol 'arch_cpu_idle' was not
declared. Should it be static?
Fix this by including linux/cpu.h to get the declaration of
arch_cpu_idle().
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: trivial@kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/17169/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Commit 1a3d59579b ("MIPS: Tidy up FPU context switching") removed
usage of ST_OFF, leaving it behind as dead code. Commit 828d1e4e98
("MIPS: Remove dead define of ST_OFF") then removed the definition of
ST_OFF from r4k_switch.S as a cleanup. However the unused definition of
ST_OFF has been left behind in r2300_switch.S. Remove it.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16239/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Move _save_fp(), _restore_fp() & _init_fpu() out of r2300_switch.S &
into r2300_fpu.S. This logically places all FP-related asm code into
r2300_fpu.S & provides consistency with R4K after the preceding commit.
Besides cleaning up this will be useful for later patches which disable
FP support.
[ralf@linux-mips.org: Fixed build issues reported by Arnd Bergmann
<arnd@arndb.de>]
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16238/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Move _save_fp(), _restore_fp(), _save_msa(), _restore_msa(),
_init_msa_upper() & _init_fpu() out of r4k_switch.S & into r4k_fpu.S.
This allows us to clean up the way in which Octeon includes the default
r4k implementations of these FP functions despite replacing resume(),
and makes CONFIG_R4K_FPU more straightforwardly represent all
configurations that have an R4K-style FPU, including Octeon.
Besides cleaning up this will be useful for later patches which disable
FP support.
[ralf@linux-mips.org: Fixed build issues reported by Arnd Bergmann
<arnd@arndb.de>]
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16237/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The kernel contains a small amount of incomplete code aimed at
supporting old R6000 CPUs. This is:
- Unused, as no machine selects CONFIG_SYS_HAS_CPU_R6000.
- Broken, since there are glaring errors such as r6000_fpu.S moving
the FCSR register to t1, then ignoring it & instead saving t0 into
struct sigcontext...
- A maintenance headache, since it's code that nobody can test which
nevertheless imposes constraints on code which it shares with other
machines.
Remove this incomplete & broken R6000 CPU support in order to clean up
and in preparation for changes which will no longer need to consider
dragging the pretense of R6000 support along with them.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16236/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The r2_decoder_tables are never modified. They are arrays of constant
values and as such should be declared const.
This change saves 256 bytes of kernel text, and 128 bytes of kernel data
(384 bytes total) on a 32r6el_defconfig (with SMP disabled)
Before:
text data bss dec hex filename
5576221 1080804 267040 6924065 69a721 vmlinux
After:
text data bss dec hex filename
5575965 1080676 267040 6923681 69a5a1 vmlinux
Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/15289/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
smp_ops providers do not modify their ops structures, so they should be
made const for robustness. Since currently the MIPS kernel is not mapped
with memory protection, this does not in itself provide any security
benefit, but it still makes sense to make this change.
There are also slight code size efficincies from the structure being
made read-only, saving 128 bytes of kernel text on a
pistachio_defconfig.
Before:
text data bss dec hex filename
7187239 1772752 470224 9430215 8fe4c7 vmlinux
After:
text data bss dec hex filename
7187111 1772752 470224 9430087 8fe447 vmlinux
Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Marcin Nowakowski <marcin.nowakowski@imgtec.com>
Cc: Bart Van Assche <bart.vanassche@sandisk.com>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Huacai Chen <chenhc@lemote.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Kevin Cernekee <cernekee@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Doug Ledford <dledford@redhat.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Joe Perches <joe@perches.com>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Steven J. Hill <steven.hill@cavium.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/16784/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
struct call_single_data is used in IPIs to transfer information between
CPUs. Its size is bigger than sizeof(unsigned long) and less than
cache line size. Currently it is not allocated with any explicit alignment
requirements. This makes it possible for allocated call_single_data to
cross two cache lines, which results in double the number of the cache lines
that need to be transferred among CPUs.
This can be fixed by requiring call_single_data to be aligned with the
size of call_single_data. Currently the size of call_single_data is the
power of 2. If we add new fields to call_single_data, we may need to
add padding to make sure the size of new definition is the power of 2
as well.
Fortunately, this is enforced by GCC, which will report bad sizes.
To set alignment requirements of call_single_data to the size of
call_single_data, a struct definition and a typedef is used.
To test the effect of the patch, I used the vm-scalability multiple
thread swap test case (swap-w-seq-mt). The test will create multiple
threads and each thread will eat memory until all RAM and part of swap
is used, so that huge number of IPIs are triggered when unmapping
memory. In the test, the throughput of memory writing improves ~5%
compared with misaligned call_single_data, because of faster IPIs.
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Huang, Ying <ying.huang@intel.com>
[ Add call_single_data_t and align with size of call_single_data. ]
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Aaron Lu <aaron.lu@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/87bmnqd6lz.fsf@yhuang-mobile.sh.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
In a recent discussion Maciej Rozycki reported that this case is
impossible.
Handle the impossible case by just returning instead of trying to
handle it. This makes static analysis simpler as it means nothing
needs to consider the impossible case after the return statement.
As the code no longer has to deal with this case remove FPE_FIXME from
the mips siginfo.h
Cc: "Maciej W. Rozycki" <macro@imgtec.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Link: http://lkml.kernel.org/r/20170718140651.15973-4-ebiederm@xmission.com
Ref: ea1b75cf91 ("signal/mips: Document a conflict with SI_USER with SIGFPE")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
While testing cpu hoptlug (cpu down and up in loops) on kernel 4.4, it was
observed that occasionally check for cpu online will fail in kernel/cpu.c,
_cpu_up:
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git/tree/kernel/cpu.c?h=v4.4.79#n485
518 /* Arch-specific enabling code. */
519 ret = __cpu_up(cpu, idle);
520
521 if (ret != 0)
522 goto out_notify;
523 BUG_ON(!cpu_online(cpu));
Reason is race between start_secondary and _cpu_up. cpu_callin_map is set
before cpu_online_mask. In __cpu_up, cpu_callin_map is waited for, but cpu
online mask is not, resulting in race in which secondary processor started
and set cpu_callin_map, but not yet set the online mask,resulting in above
BUG being hit.
Upstream differs in the area. cpu_online check is in bringup_wait_for_ap,
which is after cpu reached AP_ONLINE_IDLE,where secondary passed its start
function. Nonetheless, fix makes start_secondary safe and not depending on
other locks throughout the code. It protects as well against cpu_online
checks put in between sometimes in the future.
Fix this by moving completion after all flags are set.
Signed-off-by: Matija Glavinic Pecotic <matija.glavinic-pecotic.ext@nokia.com>
Cc: Alexander Sverdlin <alexander.sverdlin@nokia.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16925/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
struct siginfo is a union and the kernel since 2.4 has been hiding a union
tag in the high 16bits of si_code using the values:
__SI_KILL
__SI_TIMER
__SI_POLL
__SI_FAULT
__SI_CHLD
__SI_RT
__SI_MESGQ
__SI_SYS
While this looks plausible on the surface, in practice this situation has
not worked well.
- Injected positive signals are not copied to user space properly
unless they have these magic high bits set.
- Injected positive signals are not reported properly by signalfd
unless they have these magic high bits set.
- These kernel internal values leaked to userspace via ptrace_peek_siginfo
- It was possible to inject these kernel internal values and cause the
the kernel to misbehave.
- Kernel developers got confused and expected these kernel internal values
in userspace in kernel self tests.
- Kernel developers got confused and set si_code to __SI_FAULT which
is SI_USER in userspace which causes userspace to think an ordinary user
sent the signal and that it was not kernel generated.
- The values make it impossible to reorganize the code to transform
siginfo_copy_to_user into a plain copy_to_user. As si_code must
be massaged before being passed to userspace.
So remove these kernel internal si codes and make the kernel code simpler
and more maintainable.
To replace these kernel internal magic si_codes introduce the helper
function siginfo_layout, that takes a signal number and an si_code and
computes which union member of siginfo is being used. Have
siginfo_layout return an enumeration so that gcc will have enough
information to warn if a switch statement does not handle all of union
members.
A couple of architectures have a messed up ABI that defines signal
specific duplications of SI_USER which causes more special cases in
siginfo_layout than I would like. The good news is only problem
architectures pay the cost.
Update all of the code that used the previous magic __SI_ values to
use the new SIL_ values and to call siginfo_layout to get those
values. Escept where not all of the cases are handled remove the
defaults in the switch statements so that if a new case is missed in
the future the lack will show up at compile time.
Modify the code that copies siginfo si_code to userspace to just copy
the value and not cast si_code to a short first. The high bits are no
longer used to hold a magic union member.
Fixup the siginfo header files to stop including the __SI_ values in
their constants and for the headers that were missing it to properly
update the number of si_codes for each signal type.
The fixes to copy_siginfo_from_user32 implementations has the
interesting property that several of them perviously should never have
worked as the __SI_ values they depended up where kernel internal.
With that dependency gone those implementations should work much
better.
The idea of not passing the __SI_ values out to userspace and then
not reinserting them has been tested with criu and criu worked without
changes.
Ref: 2.4.0-test1
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Setting si_code to __SI_FAULT results in a userspace seeing
an si_code of 0. This is the same si_code as SI_USER. Posix
and common sense requires that SI_USER not be a signal specific
si_code. As such this use of 0 for the si_code is a pretty
horribly broken ABI.
This use of of __SI_FAULT is only a decade old. Which compared
to the other pieces of kernel code that has made this mistake
is almost yesterday.
This is probably worth fixing but I don't know mips well enough
to know what si_code to would be the proper one to use.
Cc: Ralf Baechle <ralf@linux-mips.org>
Ref: 948a34cf39 ("[MIPS] Maintain si_code field properly for FP exceptions")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Paul Burton