linux.git/arch/powerpc/sysdev/xive, branch master

treewide: refresh kmalloc_obj() conversions

2026-09-05T04:37:00+00:00

This is another run of the Coccinelle script for converting kmalloc()
family of allocations to kmalloc_obj() via the existing rules in
scripts/coccinelle/api/kmalloc_objs.cocci

This catches both the set of kmalloc() uses added since the first
kmalloc_obj() conversions in v7.0 and adds a large group missed in the
first pass due to Coccinelle not interacting well with the cleanup.h
scoped_...() family of macros[1]. I worked around this with spatch's
"--macro-file" argument to a file with all the scoped_...() macros mapped
to Coccinelle's YACFE_ITERATOR[2] as that was the closest viable control
flow indicator I could find.

Build tested allmodconfig on x86, arm64, arm, loongarch, mips, powerpc,
riscv, and s390 with no new warnings.

Link: https://lore.kernel.org/lkml/202609021314.8A9C0B8@keescook/ [1]
Link: https://github.com/coccinelle/coccinelle/blob/master/standard.h [2]
Signed-off-by: Kees Cook

powerpc/xive: defer setting cause_ipi until IPI init succeeds

2026-08-03T08:26:00+00:00

xive_smp_probe() currently assigns smp_ops->cause_ipi = xive_cause_ipi
before calling xive_init_ipis() and xive_setup_cpu_ipi().  If either
call fails, the platform probe handler returns early but cause_ipi
remains pointing to xive_cause_ipi -- which accesses per-cpu IPI data
(xc->ipi_data) that was never properly initialized, leading to
a WARN and a crash.

Move the cause_ipi assignment to after both calls succeed, so that
smp_ops->cause_ipi is only set when the IPI subsystem is fully
initialized.

Signed-off-by: Gou Hao 
Suggested-by: Cédric Le Goater 
Reviewed-by: jiazhenyuan 
Reviewed-by: Cédric Le Goater 
Signed-off-by: Madhavan Srinivasan 
Link: https://patch.msgid.link/20260727104215.184786-5-gouhao@uniontech.com

powerpc/xive: propagate IPI init errors to prevent use-after-free

2026-08-03T08:25:59+00:00

When xive_init_ipis() fails (e.g. irq_domain_alloc_irqs() fails),
the error path frees the global xive_ipis array.  However,
xive_smp_probe() previously ignored this failure and proceeded to
call xive_setup_cpu_ipi(), which dereferences the already-freed
xive_ipis pointer -- a use-after-free.

Now that xive_smp_probe() returns int (previous patch), propagate
the error from xive_init_ipis() and xive_setup_cpu_ipi() through
xive_smp_probe().  Check the return value in both pnv_smp_probe()
and pSeries_smp_probe() so that IPI setup is aborted cleanly on
failure, avoiding the use-after-free.

Fixes: 243e25112d06 ("powerpc/xive: Native exploitation of the XIVE interrupt controller")
Fixes: cbc06f051c52 ("powerpc/xive: Do not skip CPU-less nodes when creating the IPIs")
Signed-off-by: Gou Hao 
Reviewed-by: Wentao Guan 
Reviewed-by: jiazhenyuan 
Reviewed-by: Cédric Le Goater 
Signed-off-by: Madhavan Srinivasan 
Link: https://patch.msgid.link/20260727104215.184786-4-gouhao@uniontech.com

powerpc/xive: add error return value to xive_smp_probe()

2026-08-03T08:25:59+00:00

xive_smp_probe() calls xive_init_ipis() which can fail, but its
return value is currently ignored.  Change xive_smp_probe() to
return int so that errors can be propagated to callers.

This is a preparatory patch for the next one.

No functional change yet; the return value is always 0 at this point.

Signed-off-by: Gou Hao 
Reviewed-by: Wentao Guan 
Reviewed-by: jiazhenyuan 
Reviewed-by: Cédric Le Goater 
Signed-off-by: Madhavan Srinivasan 
Link: https://patch.msgid.link/20260727104215.184786-3-gouhao@uniontech.com

powerpc/xive: make xive IPI allocation NULL-safe

2026-08-03T08:25:59+00:00

__GFP_NOFAIL should not be used in new code [1].  xive_init_ipis()
allocates the xive_ipis array with __GFP_NOFAIL, which makes the
subsequent NULL check unreachable dead code.

Remove __GFP_NOFAIL so the allocation can fail, and make all xive_ipis
access paths NULL-safe:

- Return XIVE_BAD_IRQ from xive_ipi_cpu_to_irq() when xive_ipis is NULL.
- Set xive_ipis to NULL after kfree() in the error path to prevent
  use-after-free.
- Guard xive_setup_cpu_ipi() and xive_cleanup_cpu_ipi() against
  xive_ipi_irq == XIVE_BAD_IRQ to avoid dereferencing an uninitialized
  or already-freed xive_ipis array.

No functional change when allocation succeeds.

Link: https://lore.kernel.org/all/20260725202632.dcb325658896a470df91cf57@linux-foundation.org/ [1]
Fixes: 7dcc37b3eff9 ("powerpc/xive: Map one IPI interrupt per node")
Signed-off-by: Gou Hao 
Suggested-by: Andrew Morton 
Suggested-by: Cédric Le Goater 
Suggested-by: Mukesh Kumar Chaurasiya (IBM) 
Reviewed-by: Wentao Guan 
Reviewed-by: jiazhenyuan 
Reviewed-by: Mukesh Kumar Chaurasiya (IBM) 
Reviewed-by: Cédric Le Goater 
Reviewed-by: Andrew Morton 
Signed-off-by: Madhavan Srinivasan 
Link: https://patch.msgid.link/20260727104215.184786-2-gouhao@uniontech.com

powerpc/xive: Add warning if target CPU not found

2026-06-02T05:54:32+00:00

Add a warn_once to warn if the CPU target is not found. This could help
to find about any such usecase.

This is a very rare case, which either means mask was empty or
atomic update failed for all online CPUs. So it is worth printing that
path for potential fix.

Signed-off-by: Shrikanth Hegde 
Reviewed-by: Yury Norov 
Signed-off-by: Madhavan Srinivasan 
Link: https://patch.msgid.link/20260427044715.559137-5-sshegde@linux.ibm.com

Merge tag 'powerpc-7.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

2026-04-15T00:10:15+00:00

Pull powerpc updates from Madhavan Srinivasan:

 - powerpc support for huge pfnmaps

 - Cleanups to use masked user access

 - Rework pnv_ioda_pick_m64_pe() to use better bitmap API

 - Convert powerpc to AUDIT_ARCH_COMPAT_GENERIC

 - Backup region offset update to eflcorehdr

 - Fixes for wii/ps3 platform

 - Implement JIT support for private stack in powerpc

 - Implement JIT support for fsession in powerpc64 trampoline

 - Add support for instruction array and indirect jump in powerpc

 - Misc selftest fixes and cleanups

Thanks to Abhishek Dubey, Aditya Gupta, Alex Williamson, Amit Machhiwal,
Andrew Donnellan, Bartosz Golaszewski, Cédric Le Goater, Chen Ni,
Christophe Leroy (CS GROUP), Hari Bathini, J. Neuschäfer, Mukesh Kumar
Chaurasiya (IBM), Nam Cao, Nilay Shroff, Pavithra Prakash, Randy Dunlap,
Ritesh Harjani (IBM), Shrikanth Hegde, Sourabh Jain, Vaibhav Jain,
Venkat Rao Bagalkote, and Yury Norov (NVIDIA)

* tag 'powerpc-7.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (47 commits)
  mailmap: Add entry for Andrew Donnellan
  powerpc32/bpf: fix loading fsession func metadata using PPC_LI32
  selftest/bpf: Enable gotox tests for powerpc64
  powerpc64/bpf: Add support for indirect jump
  selftest/bpf: Enable instruction array test for powerpc
  powerpc/bpf: Add support for instruction array
  powerpc32/bpf: Add fsession support
  powerpc64/bpf: Implement fsession support
  selftests/bpf: Enable private stack tests for powerpc64
  powerpc64/bpf: Implement JIT support for private stack
  powerpc: pci-ioda: Optimize pnv_ioda_pick_m64_pe()
  powerpc: pci-ioda: use bitmap_alloc() in pnv_ioda_pick_m64_pe()
  powerpc/net: Inline checksum wrappers and convert to scoped user access
  powerpc/sstep: Convert to scoped user access
  powerpc/align: Convert emulate_spe() to scoped user access
  powerpc/ptrace: Convert gpr32_set_common_user() to scoped user access
  powerpc/futex: Use masked user access
  powerpc/audit: Convert powerpc to AUDIT_ARCH_COMPAT_GENERIC
  cpuidle: powerpc: avoid double clear when breaking snooze
  powerpc/ps3: spu.c: fix enum and Return kernel-doc warnings
  ...

powerpc/xive: simplify xive_spapr_debug_show()

2026-04-09T17:28:05+00:00

The function creates temporary buffer to convert xibm->bitmap to a
human-readable list before passing it to seq_printf. Drop it and print
the list by seq_printf() directly with the "%*pbl" specifier.

Reviewed-by: Shrikanth Hegde 
Acked-by: Madhavan Srinivasan  for powerpc patch
Signed-off-by: Yury Norov

powerpc/xive: rework xive_find_target_in_mask()

2026-04-01T03:51:04+00:00

Switch the function to using modern cpumask API and drop most of the
housekeeping code.

Notice, if first >= nr_cpu_ids, for_each_cpu_wrap() iterator behaves just
like for_each_cpu(), i.e. begins from 0. So even if WARN_ON() is triggered,
no special handling is needed.

Signed-off-by: Yury Norov 
Tested-by: Mukesh Kumar Chaurasiya (IBM) 
Reviewed-by: Shrikanth Hegde 
Reviewed-by: Mukesh Kumar Chaurasiya (IBM) 
Signed-off-by: Madhavan Srinivasan 
Link: https://patch.msgid.link/20260319033647.881246-3-ynorov@nvidia.com

Revert "powerpc/xive: Fix the size of the cpumask used in xive_find_target_in_mask()"

2026-04-01T03:51:04+00:00

This reverts commit a9dadc1c512807f955f0799e85830b420da47932.

The commit message states:

    When called from xive_irq_startup(), the size of the cpumask can be
    larger than nr_cpu_ids. This can result in a WARN_ON.
    [...]
    This happens because we're being called with our affinity mask set to
    irq_default_affinity. That in turn was populated using
    cpumask_setall(), which sets NR_CPUs worth of bits, not nr_cpu_ids
    worth. Finally cpumask_weight() will return > nr_cpu_ids when passed a
    mask which has > nr_cpu_ids bits set.

In modern kernel, cpumask_weight() can't return > nr_cpu_ids.

In inline case, cpumask_setall() explicitly clears all bits above
nr_cpu_ids, see commit 63355b9884b3 ("cpumask: be more careful with
'cpumask_setall()'"). So, despite that cpumask_weight() is passed
with small_cpumask_bits, which is NR_CPUS in this case, it can't
count over the nr_cpu_ids.

In outline case, cpumask_setall() may set bits beyond the limit up to
the next byte alignment, but in this case small_cpumask_bits is wired
to nr_cpu_ids, thus making overcounting impossible.

Signed-off-by: Yury Norov 
Tested-by: Mukesh Kumar Chaurasiya (IBM) 
Reviewed-by: Mukesh Kumar Chaurasiya (IBM) 
Signed-off-by: Madhavan Srinivasan 
Link: https://patch.msgid.link/20260319033647.881246-2-ynorov@nvidia.com