In preparation of next patch that will perform some additional
calculations to replace comparison, switch the use of r0 and r3
as r0 has some limitations in some instructions like 'addi/subi'.
Also remove outdated comments about the meaning of each register.
The registers are used for many things and it would be difficult
to accurately describe all things done with a given register. The
function is now small enough to get a global view without much
description.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/566af5e87685b1a85d3182549c0d520ce2d8877a.1724173828.git.christophe.leroy@csgroup.eu
At the time being, DATA TLB miss handlers use task PGDIR for user
addresses and swapper_pg_dir for kernel addresses.
Now that kernel part of swapper_pg_dir is copied into task PGDIR
at PGD allocation, it is possible to avoid the above logic and
always use task PGDIR.
But new kernel PGD entries can still be created after init, in
which case those PGD entries may miss in task PGDIR. This can be
handled in DATA TLB error handler.
However, it needs to be done in real mode because the missing
entry might be related to the stack.
So implement copy of missing PGD entry in the prolog of DATA TLB
ERROR handler just after the fixup of DAR.
Note that this is feasible because 8xx doesn't implement vmap or
ioremap with 8Mbytes pages but only 512kbytes pages which are at
PTE level.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/7a76a923d2a111f1d843d8b20b4df0c65d2f4a7b.1724173828.git.christophe.leroy@csgroup.eu
8xx boards don't have much memory, the two I know have respectively
32Mbytes and 128Mbytes, so there is no point in having 256 Mbytes of
memory for module text.
Reduce it to 32Mbytes for 8xx, that's more than enough.
Nevertheless, make it a configurable value so that it can be customised
if needed.
Also add a build verification for overlap of module execmem space
with user PMD.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/8db23b61e33a0d1913d814f94bfe71ba7ac78b0f.1724173828.git.christophe.leroy@csgroup.eu
This reverts commit bccc58986a.
When STRICT_KERNEL_RWX is selected, EXEC memory must stop where
RW memory start. When pinning iTLBs it means an 8M alignment for
RW data start. That may be acceptable on boards with a lot of
memory but one of my supported boards only has 32 Mbytes and this
forced alignment leads to a waste of almost 4 Mbytes with is more
than 10% of the total memory.
So revert commit bccc58986a ("powerpc/8xx: Always pin kernel text
TLB") but don't restore previous behaviour in ITLB miss handler
as now kernel PGD entries are copied into each process PGDIR.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/01b6780b860c8043b51a1ba9d83acfc6f2dde910.1724173828.git.christophe.leroy@csgroup.eu
Since commit 9132a2e82a ("powerpc/8xx: Define a MODULE area below
kernel text"), module exec space is below PAGE_OFFSET so not only
space above PAGE_OFFSET, but space above TASK_SIZE need to be seen
as kernel space.
Until now the problem went undetected because by default TASK_SIZE
is 0x8000000 which means address space is determined by just
checking upper address bit. But when TASK_SIZE is over 0x80000000,
PAGE_OFFSET is used for comparison, leading to thinking module
addresses are part of user space.
Fix it by using TASK_SIZE instead of PAGE_OFFSET for address
comparison.
Fixes: 9132a2e82a ("powerpc/8xx: Define a MODULE area below kernel text")
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/3f574c9845ff0a023b46cb4f38d2c45aecd769bd.1724173828.git.christophe.leroy@csgroup.eu
Commit cf209951fa ("powerpc/8xx: Map linear memory with huge pages")
introduced an initial mapping of kernel TEXT using PAGE_KERNEL_TEXT,
but the pages that contain kernel TEXT may also contain kernel RODATA,
and depending on selected debug options PAGE_KERNEL_TEXT may be either
RWX or ROX. RODATA must be writable during init because it also
contains ro_after_init data.
So use PAGE_KERNEL_X instead to be sure it is RWX.
Fixes: cf209951fa ("powerpc/8xx: Map linear memory with huge pages")
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/dac7a828d8497c4548c91840575a706657baa4f1.1724173828.git.christophe.leroy@csgroup.eu
If a function name is greater than 63 characters long, xmon command
may not find them. For example, here is a test that executed an illegal
instruction in a kernel function and one of call stack function has a
name greater than 63 characters long:
cpu 0x0: Vector: 700 (Program Check) at [c00000000a6577e0]
pc: c0000000001aacb8: check__allowed__function__name__for__symbol__r4+0x8/0x10
lr: c00000000019c1e0: check__allowed__function__name__for__symbol__r1+0x20/0x40
sp: c00000000a657a80
msr: 800000000288b033
current = 0xc00000000a439900
paca = 0xc000000003e90000 irqmask: 0x03 irq_happened: 0x01
.....
[link register ] c00000000019c1e0 check__allowed__function__name__for__symbol__r1+0x20/0x40
[c00000000a657a80] c00000000a439900 (unreliable)
[c00000000a657aa0] c0000000001021d8 check__allowed__function__name__for__symbol__r2_resolution_symbol+0x38/0x4c
[c00000000a657ac0] c00000000019b424 power_pmu_event_init+0xa4/0xa50
and when executing a dump instruction (di) command for long function
name, xmon fails to find the function symbol:
0:mon> di $check__allowed__function__name__for__symbol__r2_resolution_symbol
unknown symbol 'check__allowed__function__name__for__symbol__r2_resolution_symb'
0000000000000000 ********
This is because in scanhex(), tmpstr loop index is checked only for
a upper bound of 63.
Fix it by replacing the upper bound value with (KSYM_NAME_LEN-1).
With fix:
0:mon> di $check__allowed__function__name__for__symbol__r2_resolution_symbol
c0000000001021a0 3c4c0249 addis r2,r12,585
c0000000001021a4 3842ae60 addi r2,r2,-20896
c0000000001021a8 7c0802a6 mflr r0
c0000000001021ac 60000000 nop
.....
Reported-by: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
Closes: https://lore.kernel.org/linuxppc-dev/CANiq72=QeTgtZL4k9=4CJP6C_Hv=rh3fsn3B9S3KFoPXkyWk3w@mail.gmail.com/
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240826064217.46658-1-maddy@linux.ibm.com
These changes are for patch_instruction() uses on data. Unlike ppc64
these should not be incorrect as-is, but using the patch_uint() alias
better reflects what kind of data being patched and allows for
benchmarking the effect of different patch_* implementations (e.g.,
skipping instruction flushing when patching data).
Signed-off-by: Benjamin Gray <bgray@linux.ibm.com>
Tested-by: Hari Bathini <hbathini@linux.ibm.com>
Acked-by: Naveen N Rao <naveen@kernel.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240515024445.236364-5-bgray@linux.ibm.com
patch_instruction() is designed for patching instructions in otherwise
readonly memory. Other consumers also sometimes need to patch readonly
memory, so have abused patch_instruction() for arbitrary data patches.
This is a problem on ppc64 as patch_instruction() decides on the patch
width using the 'instruction' opcode to see if it's a prefixed
instruction. Data that triggers this can lead to larger writes, possibly
crossing a page boundary and failing the write altogether.
Introduce patch_uint(), and patch_ulong(), with aliases patch_u32(), and
patch_u64() (on ppc64) designed for aligned data patches. The patch
size is now determined by the called function, and is passed as an
additional parameter to generic internals.
While the instruction flushing is not required for data patches, it
remains unconditional in this patch. A followup series is possible if
benchmarking shows fewer flushes gives an improvement in some
data-patching workload.
ppc32 does not support prefixed instructions, so is unaffected by the
original issue. Care is taken in not exposing the size parameter in the
public (non-static) interface, so the compiler can const-propagate it
away.
Signed-off-by: Benjamin Gray <bgray@linux.ibm.com>
Reviewed-by: Hari Bathini <hbathini@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240515024445.236364-2-bgray@linux.ibm.com
Replace FB_BLANK_ constants with their counterparts from the
backlight subsystem. The values are identical, so there's no
change in functionality or semantics.
via-pmu-backlight.c already includes backlight.h where the
BACKLIGHT constants are defined.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240731130720.1148872-3-tzimmermann@suse.de
Replace FB_BLANK_ constants with their counterparts from the
backlight subsystem. The values are identical, so there's no
change in functionality or semantics.
traps.c already includes backlight.h where the BACKLIGHT
constants are defined.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240731130720.1148872-2-tzimmermann@suse.de
Use of_property_present() to test for property presence rather than
of_get_property(). This is part of a larger effort to remove callers
of of_get_property() and similar functions. of_get_property() leaks
the DT property data pointer which is a problem for dynamically
allocated nodes which may be freed.
Signed-off-by: Rob Herring (Arm) <robh@kernel.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240731191312.1710417-9-robh@kernel.org
The kernel sleep profile is no longer working due to a recursive locking
bug introduced by commit 42a20f86dc ("sched: Add wrapper for get_wchan()
to keep task blocked")
Booting with the 'profile=sleep' kernel command line option added or
executing
# echo -n sleep > /sys/kernel/profiling
after boot causes the system to lock up.
Lockdep reports
kthreadd/3 is trying to acquire lock:
ffff93ac82e08d58 (&p->pi_lock){....}-{2:2}, at: get_wchan+0x32/0x70
but task is already holding lock:
ffff93ac82e08d58 (&p->pi_lock){....}-{2:2}, at: try_to_wake_up+0x53/0x370
with the call trace being
lock_acquire+0xc8/0x2f0
get_wchan+0x32/0x70
__update_stats_enqueue_sleeper+0x151/0x430
enqueue_entity+0x4b0/0x520
enqueue_task_fair+0x92/0x6b0
ttwu_do_activate+0x73/0x140
try_to_wake_up+0x213/0x370
swake_up_locked+0x20/0x50
complete+0x2f/0x40
kthread+0xfb/0x180
However, since nobody noticed this regression for more than two years,
let's remove 'profile=sleep' support based on the assumption that nobody
needs this functionality.
Fixes: 42a20f86dc ("sched: Add wrapper for get_wchan() to keep task blocked")
Cc: stable@vger.kernel.org # v5.16+
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull x86 fixes from Thomas Gleixner:
- Prevent a deadlock on cpu_hotplug_lock in the aperf/mperf driver.
A recent change in the ACPI code which consolidated code pathes moved
the invocation of init_freq_invariance_cppc() to be moved to a CPU
hotplug handler. The first invocation on AMD CPUs ends up enabling a
static branch which dead locks because the static branch enable tries
to acquire cpu_hotplug_lock but that lock is already held write by
the hotplug machinery.
Use static_branch_enable_cpuslocked() instead and take the hotplug
lock read for the Intel code path which is invoked from the
architecture code outside of the CPU hotplug operations.
- Fix the number of reserved bits in the sev_config structure bit field
so that the bitfield does not exceed 64 bit.
- Add missing Zen5 model numbers
- Fix the alignment assumptions of pti_clone_pgtable() and
clone_entry_text() on 32-bit:
The code assumes PMD aligned code sections, but on 32-bit the kernel
entry text is not PMD aligned. So depending on the code size and
location, which is configuration and compiler dependent, entry text
can cross a PMD boundary. As the start is not PMD aligned adding PMD
size to the start address is larger than the end address which
results in partially mapped entry code for user space. That causes
endless recursion on the first entry from userspace (usually #PF).
Cure this by aligning the start address in the addition so it ends up
at the next PMD start address.
clone_entry_text() enforces PMD mapping, but on 32-bit the tail might
eventually be PTE mapped, which causes a map fail because the PMD for
the tail is not a large page mapping. Use PTI_LEVEL_KERNEL_IMAGE for
the clone() invocation which resolves to PTE on 32-bit and PMD on
64-bit.
- Zero the 8-byte case for get_user() on range check failure on 32-bit
The recend consolidation of the 8-byte get_user() case broke the
zeroing in the failure case again. Establish it by clearing ECX
before the range check and not afterwards as that obvioulsy can't be
reached when the range check fails
* tag 'x86-urgent-2024-08-04' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/uaccess: Zero the 8-byte get_range case on failure on 32-bit
x86/mm: Fix pti_clone_entry_text() for i386
x86/mm: Fix pti_clone_pgtable() alignment assumption
x86/setup: Parse the builtin command line before merging
x86/CPU/AMD: Add models 0x60-0x6f to the Zen5 range
x86/sev: Fix __reserved field in sev_config
x86/aperfmperf: Fix deadlock on cpu_hotplug_lock
Pull timer fixes from Thomas Gleixner:
"Two fixes for the timer/clocksource code:
- The recent fix to make the take over of the broadcast timer more
reliable retrieves a per CPU pointer in preemptible context.
This went unnoticed in testing as some compilers hoist the access
into the non-preemotible section where the pointer is actually
used, but obviously compilers can rightfully invoke it where the
code put it.
Move it into the non-preemptible section right to the actual usage
side to cure it.
- The clocksource watchdog is supposed to emit a warning when the
retry count is greater than one and the number of retries reaches
the limit.
The condition is backwards and warns always when the count is
greater than one. Fixup the condition to prevent spamming dmesg"
* tag 'timers-urgent-2024-08-04' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
clocksource: Fix brown-bag boolean thinko in cs_watchdog_read()
tick/broadcast: Move per CPU pointer access into the atomic section
Pull scheduler fixes from Thomas Gleixner:
- When stime is larger than rtime due to accounting imprecision, then
utime = rtime - stime becomes negative. As this is unsigned math, the
result becomes a huge positive number.
Cure it by resetting stime to rtime in that case, so utime becomes 0.
- Restore consistent state when sched_cpu_deactivate() fails.
When offlining a CPU fails in sched_cpu_deactivate() after the SMT
present counter has been decremented, then the function aborts but
fails to increment the SMT present counter and leaves it imbalanced.
Consecutive operations cause it to underflow. Add the missing fixup
for the error path.
For SMT accounting the runqueue needs to marked online again in the
error exit path to restore consistent state.
* tag 'sched-urgent-2024-08-04' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/core: Fix unbalance set_rq_online/offline() in sched_cpu_deactivate()
sched/core: Introduce sched_set_rq_on/offline() helper
sched/smt: Fix unbalance sched_smt_present dec/inc
sched/smt: Introduce sched_smt_present_inc/dec() helper
sched/cputime: Fix mul_u64_u64_div_u64() precision for cputime
Pull x86 perf fixes from Thomas Gleixner:
- Move the smp_processor_id() invocation back into the non-preemtible
region, so that the result is valid to use
- Add the missing package C2 residency counters for Sierra Forest CPUs
to make the newly added support actually useful
* tag 'perf-urgent-2024-08-04' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/x86: Fix smp_processor_id()-in-preemptible warnings
perf/x86/intel/cstate: Add pkg C2 residency counter for Sierra Forest
Pull irq fixes from Thomas Gleixner:
"A couple of fixes for interrupt chip drivers:
- Make sure to skip the clear register space in the MBIGEN driver
when calculating the node register index. Otherwise the clear
register is clobbered and the wrong node registers are accessed.
- Fix a signed/unsigned confusion in the loongarch CPU driver which
converts an error code to a huge "valid" interrupt number.
- Convert the mesion GPIO interrupt controller lock to a raw spinlock
so it works on RT.
- Add a missing static to a internal function in the pic32 EVIC
driver"
* tag 'irq-urgent-2024-08-04' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
irqchip/mbigen: Fix mbigen node address layout
irqchip/meson-gpio: Convert meson_gpio_irq_controller::lock to 'raw_spinlock_t'
irqchip/irq-pic32-evic: Add missing 'static' to internal function
irqchip/loongarch-cpu: Fix return value of lpic_gsi_to_irq()
Pull locking fixes from Thomas Gleixner:
"Two fixes for locking and jump labels:
- Ensure that the atomic_cmpxchg() conditions are correct and
evaluating to true on any non-zero value except 1. The missing
check of the return value leads to inconsisted state of the jump
label counter.
- Add a missing type conversion in the paravirt spinlock code which
makes loongson build again"
* tag 'locking-urgent-2024-08-04' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
jump_label: Fix the fix, brown paper bags galore
locking/pvqspinlock: Correct the type of "old" variable in pv_kick_node()
Commit 04f08ef291 ("arm/arm64: dts: arm: Use generic clock and
regulator nodenames") renamed nodes and created 2 "clock-24000000" nodes
(at different paths).
The kernel can't handle these duplicate names even though they are at
different paths. Fix this by renaming one of the nodes to "clock-pclk".
This name is aligned with other Arm boards (those didn't have a known
frequency to use in the node name).
Fixes: 04f08ef291 ("arm/arm64: dts: arm: Use generic clock and regulator nodenames")
Reported-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Rob Herring (Arm) <robh@kernel.org>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull smb client fixes from Steve French:
- two reparse point fixes
- minor cleanup
- additional trace point (to help debug a recent problem)
* tag '6.11-rc1-smb-client-fixes' of git://git.samba.org/sfrench/cifs-2.6:
cifs: update internal version number
smb: client: fix FSCTL_GET_REPARSE_POINT against NetApp
smb3: add dynamic tracepoints for shutdown ioctl
cifs: Remove cifs_aio_ctx
smb: client: handle lack of FSCTL_GET_REPARSE_POINT support
Pull media fixes from Mauro Carvalho Chehab:
- two Kconfig fixes
- one fix for the UVC driver addressing probing time detection of a UVC
custom controls
- one fix related to PDF generation
* tag 'media/v6.11-2' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media:
media: v4l: Fix missing tabular column hint for Y14P format
media: intel/ipu6: select AUXILIARY_BUS in Kconfig
media: ipu-bridge: fix ipu6 Kconfig dependencies
media: uvcvideo: Fix custom control mapping probing
Pull SCSI fixes from James Bottomley:
"One core change that reverts the double message print patch in sd.c
(it was causing regressions on embedded systems).
The rest are driver fixes in ufs, mpt3sas and mpi3mr"
* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
scsi: ufs: exynos: Don't resume FMP when crypto support is disabled
scsi: mpt3sas: Avoid IOMMU page faults on REPORT ZONES
scsi: mpi3mr: Avoid IOMMU page faults on REPORT ZONES
scsi: ufs: core: Do not set link to OFF state while waking up from hibernation
scsi: Revert "scsi: sd: Do not repeat the starting disk message"
scsi: ufs: core: Fix deadlock during RTC update
scsi: ufs: core: Bypass quick recovery if force reset is needed
scsi: ufs: core: Check LSDBS cap when !mcq
Pull xfs fixes from Chandan Babu:
- Fix memory leak when corruption is detected during scrubbing parent
pointers
- Allow SECURE namespace xattrs to use reserved block pool to in order
to prevent ENOSPC
- Save stack space by passing tracepoint's char array to file_path()
instead of another stack variable
- Remove unused parameter in macro XFS_DQUOT_LOGRES
- Replace comma with semicolon in a couple of places
* tag 'xfs-6.11-fixes-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
xfs: convert comma to semicolon
xfs: convert comma to semicolon
xfs: remove unused parameter in macro XFS_DQUOT_LOGRES
xfs: fix file_path handling in tracepoints
xfs: allow SECURE namespace xattrs to use reserved block pool
xfs: fix a memory leak
Pull parisc architecture fixes from Helge Deller:
- fix unaligned memory accesses when calling BPF functions
- adjust memory size constants to fix possible DMA corruptions
* tag 'parisc-for-6.11-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
parisc: fix a possible DMA corruption
parisc: fix unaligned accesses in BPF
The runtime constants linker script depended on documented linker
behavior [1]:
"If an output section’s name is the same as the input section’s name
and is representable as a C identifier, then the linker will
automatically PROVIDE two symbols: __start_SECNAME and __stop_SECNAME,
where SECNAME is the name of the section. These indicate the start
address and end address of the output section respectively"
to just automatically define the symbol names for the bounds of the
runtime constant arrays.
It turns out that this isn't actually something we can rely on, with old
linkers not generating these automatic symbols. It looks to have been
introduced in binutils-2.29 back in 2017, and we still support building
with versions all the way back to binutils-2.25 (from 2015).
And yes, Oleg actually seems to be using such ancient versions of
binutils.
So instead of depending on the implicit symbols from "section names
match and are representable C identifiers", just do this all manually.
It's not like it causes us any extra pain, we already have to do that
for all the other sections that we use that often have special
characters in them.
Reported-and-tested-by: Oleg Nesterov <oleg@redhat.com>
Link: https://sourceware.org/binutils/docs/ld/Input-Section-Example.html [1]
Link: https://lore.kernel.org/all/20240802114518.GA20924@redhat.com/
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
