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Linux kernel
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Pull powerpc fixes from Michael Ellerman:
- Fix crashes coming out of nap on 32-bit Book3s (eg. powerbooks).
- Fix critical and debug interrupts on BookE, seen as crashes when
using ptrace.
- Fix an oops when running an SMP kernel on a UP system.
- Update pseries LPAR security flavor after partition migration.
- Fix an oops when using kprobes on BookE.
- Fix oops on 32-bit pmac by not calling do_IRQ() from
timer_interrupt().
- Fix softlockups on CPU hotplug into a CPU-less node with xive (P9).
Thanks to Cédric Le Goater, Christophe Leroy, Finn Thain, Geetika
Moolchandani, Laurent Dufour, Laurent Vivier, Nicholas Piggin, Pu Lehui,
Radu Rendec, Srikar Dronamraju, and Stan Johnson.
* tag 'powerpc-5.14-5' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc/xive: Do not skip CPU-less nodes when creating the IPIs
powerpc/interrupt: Do not call single_step_exception() from other exceptions
powerpc/interrupt: Fix OOPS by not calling do_IRQ() from timer_interrupt()
powerpc/kprobes: Fix kprobe Oops happens in booke
powerpc/pseries: Fix update of LPAR security flavor after LPM
powerpc/smp: Fix OOPS in topology_init()
powerpc/32: Fix critical and debug interrupts on BOOKE
powerpc/32s: Fix napping restore in data storage interrupt (DSI)
Pull irq fixes from Thomas Gleixner:
"A set of fixes for PCI/MSI and x86 interrupt startup:
- Mask all MSI-X entries when enabling MSI-X otherwise stale unmasked
entries stay around e.g. when a crashkernel is booted.
- Enforce masking of a MSI-X table entry when updating it, which
mandatory according to speification
- Ensure that writes to MSI[-X} tables are flushed.
- Prevent invalid bits being set in the MSI mask register
- Properly serialize modifications to the mask cache and the mask
register for multi-MSI.
- Cure the violation of the affinity setting rules on X86 during
interrupt startup which can cause lost and stale interrupts. Move
the initial affinity setting ahead of actualy enabling the
interrupt.
- Ensure that MSI interrupts are completely torn down before freeing
them in the error handling case.
- Prevent an array out of bounds access in the irq timings code"
* tag 'irq-urgent-2021-08-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
driver core: Add missing kernel doc for device::msi_lock
genirq/msi: Ensure deactivation on teardown
genirq/timings: Prevent potential array overflow in __irq_timings_store()
x86/msi: Force affinity setup before startup
x86/ioapic: Force affinity setup before startup
genirq: Provide IRQCHIP_AFFINITY_PRE_STARTUP
PCI/MSI: Protect msi_desc::masked for multi-MSI
PCI/MSI: Use msi_mask_irq() in pci_msi_shutdown()
PCI/MSI: Correct misleading comments
PCI/MSI: Do not set invalid bits in MSI mask
PCI/MSI: Enforce MSI[X] entry updates to be visible
PCI/MSI: Enforce that MSI-X table entry is masked for update
PCI/MSI: Mask all unused MSI-X entries
PCI/MSI: Enable and mask MSI-X early
On PowerVM, CPU-less nodes can be populated with hot-plugged CPUs at
runtime. Today, the IPI is not created for such nodes, and hot-plugged
CPUs use a bogus IPI, which leads to soft lockups.
We can not directly allocate and request the IPI on demand because
bringup_up() is called under the IRQ sparse lock. The alternative is
to allocate the IPIs for all possible nodes at startup and to request
the mapping on demand when the first CPU of a node is brought up.
Fixes: 7dcc37b3eff9 ("powerpc/xive: Map one IPI interrupt per node")
Cc: stable@vger.kernel.org # v5.13
Reported-by: Geetika Moolchandani <Geetika.Moolchandani1@ibm.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Tested-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Tested-by: Laurent Vivier <lvivier@redhat.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210807072057.184698-1-clg@kaod.org
Pull locking fix from Borislav Petkov:
- Fix a CONFIG symbol's spelling
* tag 'locking_urgent_for_v5.14_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
locking/rtmutex: Use the correct rtmutex debugging config option
Fixes: 77e89afc25f3 ("PCI/MSI: Protect msi_desc::masked for multi-MSI")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
single_step_exception() is called by emulate_single_step() which
is called from (at least) alignment exception() handler and
program_check_exception() handler.
Redefine it as a regular __single_step_exception() which is called
by both single_step_exception() handler and emulate_single_step()
function.
Fixes: 3a96570ffceb ("powerpc: convert interrupt handlers to use wrappers")
Cc: stable@vger.kernel.org # v5.12+
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/aed174f5cbc06f2cf95233c071d8aac948e46043.1628611921.git.christophe.leroy@csgroup.eu
Pull EFI fixes from Borislav Petkov:
"A batch of fixes for the arm64 stub image loader:
- fix a logic bug that can make the random page allocator fail
spuriously
- force reallocation of the Image when it overlaps with firmware
reserved memory regions
- fix an oversight that defeated on optimization introduced earlier
where images loaded at a suitable offset are never moved if booting
without randomization
- complain about images that were not loaded at the right offset by
the firmware image loader"
* tag 'efi_urgent_for_v5.14_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
efi/libstub: arm64: Double check image alignment at entry
efi/libstub: arm64: Warn when efi_random_alloc() fails
efi/libstub: arm64: Relax 2M alignment again for relocatable kernels
efi/libstub: arm64: Force Image reallocation if BSS was not reserved
arm64: efi: kaslr: Fix occasional random alloc (and boot) failure
It's CONFIG_DEBUG_RT_MUTEXES not CONFIG_DEBUG_RT_MUTEX.
Fixes: f7efc4799f81 ("locking/rtmutex: Inline chainwalk depth check")
Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Will Deacon <will@kernel.org>
Acked-by: Boqun Feng <boqun.feng@gmail.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20210731123011.4555-1-thunder.leizhen@huawei.com
msi_domain_alloc_irqs() invokes irq_domain_activate_irq(), but
msi_domain_free_irqs() does not enforce deactivation before tearing down
the interrupts.
This happens when PCI/MSI interrupts are set up and never used before being
torn down again, e.g. in error handling pathes. The only place which cleans
that up is the error handling path in msi_domain_alloc_irqs().
Move the cleanup from msi_domain_alloc_irqs() into msi_domain_free_irqs()
to cure that.
Fixes: f3b0946d629c ("genirq/msi: Make sure PCI MSIs are activated early")
Signed-off-by: Bixuan Cui <cuibixuan@huawei.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20210518033117.78104-1-cuibixuan@huawei.com
An interrupt handler shall not be called from another interrupt
handler otherwise this leads to problems like the following:
Kernel attempted to write user page (afd4fa84) - exploit attempt? (uid: 1000)
------------[ cut here ]------------
Bug: Write fault blocked by KUAP!
WARNING: CPU: 0 PID: 1617 at arch/powerpc/mm/fault.c:230 do_page_fault+0x484/0x720
Modules linked in:
CPU: 0 PID: 1617 Comm: sshd Tainted: G W 5.13.0-pmac-00010-g8393422eb77 #7
NIP: c001b77c LR: c001b77c CTR: 00000000
REGS: cb9e5bc0 TRAP: 0700 Tainted: G W (5.13.0-pmac-00010-g8393422eb77)
MSR: 00021032 <ME,IR,DR,RI> CR: 24942424 XER: 00000000
GPR00: c001b77c cb9e5c80 c1582c00 00000021 3ffffbff 085b0000 00000027 c8eb644c
GPR08: 00000023 00000000 00000000 00000000 24942424 0063f8c8 00000000 000186a0
GPR16: afd52dd4 afd52dd0 afd52dcc afd52dc8 0065a990 c07640c4 cb9e5e98 cb9e5e90
GPR24: 00000040 afd4fa96 00000040 02000000 c1fda6c0 afd4fa84 00000300 cb9e5cc0
NIP [c001b77c] do_page_fault+0x484/0x720
LR [c001b77c] do_page_fault+0x484/0x720
Call Trace:
[cb9e5c80] [c001b77c] do_page_fault+0x484/0x720 (unreliable)
[cb9e5cb0] [c000424c] DataAccess_virt+0xd4/0xe4
--- interrupt: 300 at __copy_tofrom_user+0x110/0x20c
NIP: c001f9b4 LR: c03250a0 CTR: 00000004
REGS: cb9e5cc0 TRAP: 0300 Tainted: G W (5.13.0-pmac-00010-g8393422eb77)
MSR: 00009032 <EE,ME,IR,DR,RI> CR: 48028468 XER: 20000000
DAR: afd4fa84 DSISR: 0a000000
GPR00: 20726f6f cb9e5d80 c1582c00 00000004 cb9e5e3a 00000016 afd4fa80 00000000
GPR08: 3835202d 72777872 2d78722d 00000004 28028464 0063f8c8 00000000 000186a0
GPR16: afd52dd4 afd52dd0 afd52dcc afd52dc8 0065a990 c07640c4 cb9e5e98 cb9e5e90
GPR24: 00000040 afd4fa96 00000040 cb9e5e0c 00000daa a0000000 cb9e5e98 afd4fa56
NIP [c001f9b4] __copy_tofrom_user+0x110/0x20c
LR [c03250a0] _copy_to_iter+0x144/0x990
--- interrupt: 300
[cb9e5d80] [c03e89c0] n_tty_read+0xa4/0x598 (unreliable)
[cb9e5df0] [c03e2a0c] tty_read+0xdc/0x2b4
[cb9e5e80] [c0156bf8] vfs_read+0x274/0x340
[cb9e5f00] [c01571ac] ksys_read+0x70/0x118
[cb9e5f30] [c0016048] ret_from_syscall+0x0/0x28
--- interrupt: c00 at 0xa7855c88
NIP: a7855c88 LR: a7855c5c CTR: 00000000
REGS: cb9e5f40 TRAP: 0c00 Tainted: G W (5.13.0-pmac-00010-g8393422eb77)
MSR: 0000d032 <EE,PR,ME,IR,DR,RI> CR: 2402446c XER: 00000000
GPR00: 00000003 afd4ec70 a72137d0 0000000b afd4ecac 00004000 0065a990 00000800
GPR08: 00000000 a7947930 00000000 00000004 c15831b0 0063f8c8 00000000 000186a0
GPR16: afd52dd4 afd52dd0 afd52dcc afd52dc8 0065a990 0065a9e0 00000001 0065fac0
GPR24: 00000000 00000089 00664050 00000000 00668e30 a720c8dc a7943ff4 0065f9b0
NIP [a7855c88] 0xa7855c88
LR [a7855c5c] 0xa7855c5c
--- interrupt: c00
Instruction dump:
3884aa88 38630178 48076861 807f0080 48042e45 2f830000 419e0148 3c80c079
3c60c076 38841be4 386301c0 4801f705 <0fe00000> 3860000b 4bfffe30 3c80c06b
---[ end trace fd69b91a8046c2e5 ]---
Here the problem is that by re-enterring an exception handler,
kuap_save_and_lock() is called a second time with this time KUAP
access locked, leading to regs->kuap being overwritten hence
KUAP not being unlocked at exception exit as expected.
Do not call do_IRQ() from timer_interrupt() directly. Instead,
redefine do_IRQ() as a standard function named __do_IRQ(), and
call it from both do_IRQ() and time_interrupt() handlers.
Fixes: 3a96570ffceb ("powerpc: convert interrupt handlers to use wrappers")
Cc: stable@vger.kernel.org # v5.12+
Reported-by: Stan Johnson <userm57@yahoo.com>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/c17d234f4927d39a1d7100864a8e1145323d33a0.1628611927.git.christophe.leroy@csgroup.eu
Pull x86 fixes from Borislav Petkov:
"Two fixes:
- An objdump checker fix to ignore parenthesized strings in the
objdump version
- Fix resctrl default monitoring groups reporting when new subgroups
get created"
* tag 'x86_urgent_for_v5.14_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/resctrl: Fix default monitoring groups reporting
x86/tools: Fix objdump version check again
Pull EFI fixes from Ard Biesheuvel:
A batch of fixes for the arm64 stub image loader:
- fix a logic bug that can make the random page allocator fail
spuriously
- force reallocation of the Image when it overlaps with firmware
reserved memory regions
- fix an oversight that defeated on optimization introduced earlier
where images loaded at a suitable offset are never moved if booting
without randomization
- complain about images that were not loaded at the right offset by the
firmware image loader.
Link: https://lore.kernel.org/r/20210803091215.2566-1-ardb@kernel.org
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