Pull last (?) hotfixes from Andrew Morton: "26 hotfixes. 8 are for issues which were introduced during this -rc cycle, 18 are for earlier issues, and are cc:stable" * tag 'mm-hotfixes-stable-2022-09-26' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (26 commits) x86/uaccess: avoid check_object_size() in copy_from_user_nmi() mm/page_isolation: fix isolate_single_pageblock() isolation behavior mm,hwpoison: check mm when killing accessing process mm/hugetlb: correct demote page offset logic mm: prevent page_frag_alloc() from corrupting the memory mm: bring back update_mmu_cache() to finish_fault() frontswap: don't call ->init if no ops are registered mm/huge_memory: use pfn_to_online_page() in split_huge_pages_all() mm: fix madivse_pageout mishandling on non-LRU page powerpc/64s/radix: don't need to broadcast IPI for radix pmd collapse flush mm: gup: fix the fast GUP race against THP collapse mm: fix dereferencing possible ERR_PTR vmscan: check folio_test_private(), not folio_get_private() mm: fix VM_BUG_ON in __delete_from_swap_cache() tools: fix compilation after gfp_types.h split mm/damon/dbgfs: fix memory leak when using debugfs_lookup() mm/migrate_device.c: copy pte dirty bit to page mm/migrate_device.c: add missing flush_cache_page() mm/migrate_device.c: flush TLB while holding PTL x86/mm: disable instrumentations of mm/pgprot.c ...
The IPI broadcast is used to serialize against fast-GUP, but fast-GUP will move to use RCU instead of disabling local interrupts in fast-GUP. Using an IPI is the old-styled way of serializing against fast-GUP although it still works as expected now. And fast-GUP now fixed the potential race with THP collapse by checking whether PMD is changed or not. So IPI broadcast in radix pmd collapse flush is not necessary anymore. But it is still needed for hash TLB. Link: https://lkml.kernel.org/r/20220907180144.555485-2-shy828301@gmail.com Suggested-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Yang Shi <shy828301@gmail.com> Acked-by: David Hildenbrand <david@redhat.com> Acked-by: Peter Xu <peterx@redhat.com> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Hugh Dickins <hughd@google.com> Cc: Jason Gunthorpe <jgg@nvidia.com> Cc: John Hubbard <jhubbard@nvidia.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Pull powerpc fix from Michael Ellerman: - Fix crashes on bare metal due to the new plkps driver trying to probe and call the hypervisor on non-pseries machines. Thanks to Nathan Chancellor and Dan Horák. * tag 'powerpc-6.0-5' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: powerpc/pseries: Fix plpks crash on non-pseries
Pull SOFTIRQ_ON_OWN_STACK rework from Arnd Bergmann:
"Just one fixup patch, reworking the softirq_on_own_stack logic for
preempt-rt kernels as discussed in
https://lore.kernel.org/all/CAHk-=wgZSD3W2y6yczad2Am=EfHYyiPzTn3CfXxrriJf9i5W5w@mail.gmail.com/"
* tag 'asm-generic-fixes-6.0-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic:
asm-generic: Conditionally enable do_softirq_own_stack() via Kconfig.
As reported[1] by Nathan, the recently added plpks driver will crash if
it's built into the kernel and booted on a non-pseries machine, eg
powernv:
kernel BUG at arch/powerpc/kernel/syscall.c:39!
Oops: Exception in kernel mode, sig: 5 [#1]
LE PAGE_SIZE=64K MMU=Radix SMP NR_CPUS=2048 NUMA PowerNV
...
NIP system_call_exception+0x90/0x3d0
LR system_call_common+0xec/0x250
Call Trace:
0xc0000000035c3e10 (unreliable)
system_call_common+0xec/0x250
--- interrupt: c00 at plpar_hcall+0x38/0x60
NIP: c0000000000e4300 LR: c00000000202945c CTR: 0000000000000000
REGS: c0000000035c3e80 TRAP: 0c00 Not tainted (6.0.0-rc4)
MSR: 9000000002009033 <SF,HV,VEC,EE,ME,IR,DR,RI,LE> CR: 28000284 XER: 00000000
...
NIP plpar_hcall+0x38/0x60
LR pseries_plpks_init+0x64/0x23c
--- interrupt: c00
On powernv Linux is the hypervisor, so a hypercall just ends up going to
the syscall path, which BUGs if the syscall (hypercall) didn't come from
userspace.
The fix is simply to not probe the plpks driver on non-pseries machines.
[1] https://lore.kernel.org/linuxppc-dev/Yxe06fbq18Wv9y3W@dev-arch.thelio-3990X/
Fixes: 2454a7af0f2a ("powerpc/pseries: define driver for Platform KeyStore")
Reported-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Tested-by: Dan Horák <dan@danny.cz>
Reviewed-by: Dan Horák <dan@danny.cz>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Link: https://lore.kernel.org/r/20220907065038.1604504-1-mpe@ellerman.id.au
Remove the CONFIG_PREEMPT_RT symbol from the ifdef around do_softirq_own_stack() and move it to Kconfig instead. Enable softirq stacks based on SOFTIRQ_ON_OWN_STACK which depends on HAVE_SOFTIRQ_ON_OWN_STACK and its default value is set to !PREEMPT_RT. This ensures that softirq stacks are not used on PREEMPT_RT and avoids a 'select' statement on an option which has a 'depends' statement. Link: https://lore.kernel.org/YvN5E%2FPrHfUhggr7@linutronix.de Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Clang warns:
arch/powerpc/platforms/pseries/papr_scm.c:492:6: warning: variable 'rc' is used uninitialized whenever 'if' condition is true [-Wsometimes-uninitialized]
if (!p->stat_buffer_len)
^~~~~~~~~~~~~~~~~~~
arch/powerpc/platforms/pseries/papr_scm.c:523:64: note: uninitialized use occurs here
dev_info(&p->pdev->dev, "nvdimm pmu didn't register rc=%d\n", rc);
^~
include/linux/dev_printk.h:150:67: note: expanded from macro 'dev_info'
dev_printk_index_wrap(_dev_info, KERN_INFO, dev, dev_fmt(fmt), ##__VA_ARGS__)
^~~~~~~~~~~
include/linux/dev_printk.h:110:23: note: expanded from macro 'dev_printk_index_wrap'
_p_func(dev, fmt, ##__VA_ARGS__); \
^~~~~~~~~~~
arch/powerpc/platforms/pseries/papr_scm.c:492:2: note: remove the 'if' if its condition is always false
if (!p->stat_buffer_len)
^~~~~~~~~~~~~~~~~~~~~~~~
arch/powerpc/platforms/pseries/papr_scm.c:484:8: note: initialize the variable 'rc' to silence this warning
int rc, nodeid;
^
= 0
1 warning generated.
The call to papr_scm_pmu_check_events() was eliminated but a return code
was not added to the if statement. Add the same return code from
papr_scm_pmu_check_events() for this condition so there is no more
warning.
Fixes: 9b1ac04698a4 ("powerpc/papr_scm: Fix nvdimm event mappings")
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://github.com/ClangBuiltLinux/linux/issues/1701
Link: https://lore.kernel.org/r/20220830151256.1473169-1-nathan@kernel.org
This reverts commit ef5b570d3700fbb8628a58da0487486ceeb713cd.
Zhouyi reported that commit is causing crashes when running rcutorture
with KASAN enabled:
BUG: using smp_processor_id() in preemptible [00000000] code: rcu_torture_rea/100
caller is rcu_preempt_deferred_qs_irqrestore+0x74/0xed0
CPU: 4 PID: 100 Comm: rcu_torture_rea Tainted: G W 5.19.0-rc5-next-20220708-dirty #253
Call Trace:
dump_stack_lvl+0xbc/0x108 (unreliable)
check_preemption_disabled+0x154/0x160
rcu_preempt_deferred_qs_irqrestore+0x74/0xed0
__rcu_read_unlock+0x290/0x3b0
rcu_torture_read_unlock+0x30/0xb0
rcutorture_one_extend+0x198/0x810
rcu_torture_one_read+0x58c/0xc90
rcu_torture_reader+0x12c/0x360
kthread+0x1e8/0x220
ret_from_kernel_thread+0x5c/0x64
KASAN will generate instrumentation instructions around the
WRITE_ONCE(local_paca->irq_soft_mask, mask):
0xc000000000295cb0 <+0>: addis r2,r12,774
0xc000000000295cb4 <+4>: addi r2,r2,16464
0xc000000000295cb8 <+8>: mflr r0
0xc000000000295cbc <+12>: bl 0xc00000000008bb4c <mcount>
0xc000000000295cc0 <+16>: mflr r0
0xc000000000295cc4 <+20>: std r31,-8(r1)
0xc000000000295cc8 <+24>: addi r3,r13,2354
0xc000000000295ccc <+28>: mr r31,r13
0xc000000000295cd0 <+32>: std r0,16(r1)
0xc000000000295cd4 <+36>: stdu r1,-48(r1)
0xc000000000295cd8 <+40>: bl 0xc000000000609b98 <__asan_store1+8>
0xc000000000295cdc <+44>: nop
0xc000000000295ce0 <+48>: li r9,1
0xc000000000295ce4 <+52>: stb r9,2354(r31)
0xc000000000295ce8 <+56>: addi r1,r1,48
0xc000000000295cec <+60>: ld r0,16(r1)
0xc000000000295cf0 <+64>: ld r31,-8(r1)
0xc000000000295cf4 <+68>: mtlr r0
If there is a context switch before "stb r9,2354(r31)", r31 may
not equal to r13, in such case, irq soft mask will not work.
The usual solution of marking the code ineligible for instrumentation
forces the code out-of-line, which we would prefer to avoid. Christophe
proposed a partial revert, but Nick raised some concerns with that. So
for now do a full revert.
Reported-by: Zhouyi Zhou <zhouzhouyi@gmail.com>
[mpe: Construct change log based on Zhouyi's original report]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220831131052.42250-1-mpe@ellerman.id.au
As reported by Zhouyi Zhou, WRITE_ONCE() is not atomic
as expected when KASAN or KCSAN are compiled in.
Fix it by re-implementing it using inline assembly.
Fixes: 077fc62b2b66 ("powerpc/irq: remove inline assembly in hard_irq_disable macro")
Reported-by: Zhouyi Zhou <zhouzhouyi@gmail.com>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/a8298991b3df049a54ee8e558838e34265812014.1661272586.git.christophe.leroy@csgroup.eu
The semi-recent changes to MSR handling when entering RTAS (firmware)
cause crashes on IBM Cell machines. An example trace:
kernel tried to execute user page (2fff01a8) - exploit attempt? (uid: 0)
BUG: Unable to handle kernel instruction fetch
Faulting instruction address: 0x2fff01a8
Oops: Kernel access of bad area, sig: 11 [#1]
BE PAGE_SIZE=64K MMU=Hash SMP NR_CPUS=4 NUMA Cell
Modules linked in:
CPU: 0 PID: 0 Comm: swapper/0 Tainted: G W 6.0.0-rc2-00433-gede0a8d3307a #207
NIP: 000000002fff01a8 LR: 0000000000032608 CTR: 0000000000000000
REGS: c0000000015236b0 TRAP: 0400 Tainted: G W (6.0.0-rc2-00433-gede0a8d3307a)
MSR: 0000000008001002 <ME,RI> CR: 00000000 XER: 20000000
...
NIP 0x2fff01a8
LR 0x32608
Call Trace:
0xc00000000143c5f8 (unreliable)
.rtas_call+0x224/0x320
.rtas_get_boot_time+0x70/0x150
.read_persistent_clock64+0x114/0x140
.read_persistent_wall_and_boot_offset+0x24/0x80
.timekeeping_init+0x40/0x29c
.start_kernel+0x674/0x8f0
start_here_common+0x1c/0x50
Unlike PAPR platforms where RTAS is only used in guests, on the IBM Cell
machines Linux runs with MSR[HV] set but also uses RTAS, provided by
SLOF.
Fix it by copying the MSR[HV] bit from the MSR value we've just read
using mfmsr into the value used for RTAS.
It seems like we could also fix it using an #ifdef CELL to set MSR[HV],
but that doesn't work because it's possible to build a single kernel
image that runs on both Cell native and pseries.
Fixes: b6b1c3ce06ca ("powerpc/rtas: Keep MSR[RI] set when calling RTAS")
Cc: stable@vger.kernel.org # v5.19+
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Jordan Niethe <jniethe5@gmail.com>
Link: https://lore.kernel.org/r/20220823115952.1203106-2-mpe@ellerman.id.au