[ Upstream commit 271208ee5e ]
Using memcpy() isn't safe when buf is identical to rtas_err_buf, which
can happen during boot before slab is up. Full context which may not
be obvious from the diff:
if (altbuf) {
buf = altbuf;
} else {
buf = rtas_err_buf;
if (slab_is_available())
buf = kmalloc(RTAS_ERROR_LOG_MAX, GFP_ATOMIC);
}
if (buf)
memcpy(buf, rtas_err_buf, RTAS_ERROR_LOG_MAX);
This was found by inspection and I'm not aware of it causing problems
in practice. It appears to have been introduced by commit
033ef338b6 ("powerpc: Merge rtas.c into arch/powerpc/kernel"); the
old ppc64 version of this code did not have this problem.
Use memmove() instead.
Fixes: 033ef338b6 ("powerpc: Merge rtas.c into arch/powerpc/kernel")
Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
Reviewed-by: Andrew Donnellan <ajd@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230220-rtas-queue-for-6-4-v1-2-010e4416f13f@linux.ibm.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 1c6b5a7e74 ]
PAPR interface currently supports two different ways of communicating resource
grouping details to the OS. These are referred to as Form 0 and Form 1
associativity grouping. Form 0 is the older format and is now considered
deprecated. This patch adds another resource grouping named FORM2.
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210812132223.225214-6-aneesh.kumar@linux.ibm.com
Stable-dep-of: b277fc793d ("powerpc/papr_scm: Update the NUMA distance table for the target node")
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit fd72761894 upstream.
powerpc sets up PF_KTHREAD and PF_IO_WORKER with a NULL pt_regs, which
from my (arguably very short) checking is not commonly done for other
archs. This is fine, except when PF_IO_WORKER's have been created and
the task does something that causes a coredump to be generated. Then we
get this crash:
Kernel attempted to read user page (160) - exploit attempt? (uid: 1000)
BUG: Kernel NULL pointer dereference on read at 0x00000160
Faulting instruction address: 0xc0000000000c3a60
Oops: Kernel access of bad area, sig: 11 [#1]
LE PAGE_SIZE=64K MMU=Radix SMP NR_CPUS=32 NUMA pSeries
Modules linked in: bochs drm_vram_helper drm_kms_helper xts binfmt_misc ecb ctr syscopyarea sysfillrect cbc sysimgblt drm_ttm_helper aes_generic ttm sg libaes evdev joydev virtio_balloon vmx_crypto gf128mul drm dm_mod fuse loop configfs drm_panel_orientation_quirks ip_tables x_tables autofs4 hid_generic usbhid hid xhci_pci xhci_hcd usbcore usb_common sd_mod
CPU: 1 PID: 1982 Comm: ppc-crash Not tainted 6.3.0-rc2+ #88
Hardware name: IBM pSeries (emulated by qemu) POWER9 (raw) 0x4e1202 0xf000005 of:SLOF,HEAD hv:linux,kvm pSeries
NIP: c0000000000c3a60 LR: c000000000039944 CTR: c0000000000398e0
REGS: c0000000041833b0 TRAP: 0300 Not tainted (6.3.0-rc2+)
MSR: 800000000280b033 <SF,VEC,VSX,EE,FP,ME,IR,DR,RI,LE> CR: 88082828 XER: 200400f8
...
NIP memcpy_power7+0x200/0x7d0
LR ppr_get+0x64/0xb0
Call Trace:
ppr_get+0x40/0xb0 (unreliable)
__regset_get+0x180/0x1f0
regset_get_alloc+0x64/0x90
elf_core_dump+0xb98/0x1b60
do_coredump+0x1c34/0x24a0
get_signal+0x71c/0x1410
do_notify_resume+0x140/0x6f0
interrupt_exit_user_prepare_main+0x29c/0x320
interrupt_exit_user_prepare+0x6c/0xa0
interrupt_return_srr_user+0x8/0x138
Because ppr_get() is trying to copy from a PF_IO_WORKER with a NULL
pt_regs.
Check for a valid pt_regs in both ppc_get/ppr_set, and return an error
if not set. The actual error value doesn't seem to be important here, so
just pick -EINVAL.
Fixes: fa439810cc ("powerpc/ptrace: Enable support for NT_PPPC_TAR, NT_PPC_PPR, NT_PPC_DSCR")
Cc: stable@vger.kernel.org # v4.8+
Signed-off-by: Jens Axboe <axboe@kernel.dk>
[mpe: Trim oops in change log, add Fixes & Cc stable]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/d9f63344-fe7c-56ae-b420-4a1a04a2ae4c@kernel.dk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 07b050f929 upstream.
Relocatable kernels must not discard relocations, they need to be
processed at runtime. As such they are included for CONFIG_RELOCATABLE
builds in the powerpc linker script (line 340).
However they are also unconditionally discarded later in the
script (line 414). Previously that worked because the earlier inclusion
superseded the discard.
However commit 99cb0d917f ("arch: fix broken BuildID for arm64 and
riscv") introduced an earlier use of DISCARD as part of the RO_DATA
macro (line 137). With binutils < 2.36 that causes the DISCARD
directives later in the script to be applied earlier, causing .rela* to
actually be discarded at link time, leading to build warnings and a
kernel that doesn't boot:
ld: warning: discarding dynamic section .rela.init.rodata
Fix it by conditionally discarding .rela* only when CONFIG_RELOCATABLE
is disabled.
Fixes: 99cb0d917f ("arch: fix broken BuildID for arm64 and riscv")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20230105132349.384666-2-mpe@ellerman.id.au
Signed-off-by: Tom Saeger <tom.saeger@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 4b9880dbf3 upstream.
The powerpc linker script explicitly includes .exit.text, because
otherwise the link fails due to references from __bug_table and
__ex_table. The code is freed (discarded) at runtime along with
.init.text and data.
That has worked in the past despite powerpc not defining
RUNTIME_DISCARD_EXIT because DISCARDS appears late in the powerpc linker
script (line 410), and the explicit inclusion of .exit.text
earlier (line 280) supersedes the discard.
However commit 99cb0d917f ("arch: fix broken BuildID for arm64 and
riscv") introduced an earlier use of DISCARD as part of the RO_DATA
macro (line 136). With binutils < 2.36 that causes the DISCARD
directives later in the script to be applied earlier [1], causing
.exit.text to actually be discarded at link time, leading to build
errors:
'.exit.text' referenced in section '__bug_table' of crypto/algboss.o: defined in
discarded section '.exit.text' of crypto/algboss.o
'.exit.text' referenced in section '__ex_table' of drivers/nvdimm/core.o: defined in
discarded section '.exit.text' of drivers/nvdimm/core.o
Fix it by defining RUNTIME_DISCARD_EXIT, which causes the generic
DISCARDS macro to not include .exit.text at all.
1: https://lore.kernel.org/lkml/87fscp2v7k.fsf@igel.home/
Fixes: 99cb0d917f ("arch: fix broken BuildID for arm64 and riscv")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20230105132349.384666-1-mpe@ellerman.id.au
Signed-off-by: Tom Saeger <tom.saeger@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 2a7ce82dc4 ]
In order for KCSAN to increase its likelihood of observing a data race,
it sets a watchpoint on memory accesses and stalls, allowing for
detection of conflicting accesses by other kernel threads or interrupts.
Stalls are implemented by injecting a call to udelay in instrumented code.
To prevent recursive instrumentation, exclude udelay from being instrumented.
Signed-off-by: Rohan McLure <rmclure@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20230206021801.105268-3-rmclure@linux.ibm.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 9efcdaac36 ]
When a PCI error is encountered 6th time in an hour we
set the channel state to perm_failure and notify the
driver about the permanent failure.
However, after upstream commit 38ddc01147 ("powerpc/eeh:
Make permanently failed devices non-actionable"), EEH handler
stops calling any routine once the device is marked as
permanent failure. This issue can lead to fatal consequences
like kernel hang with certain PCI devices.
Following log is observed with lpfc driver, with and without
this change, Without this change kernel hangs, If PCI error
is encountered 6 times for a device in an hour.
Without the change
EEH: Beginning: 'error_detected(permanent failure)'
PCI 0132:60:00.0#600000: EEH: not actionable (1,1,1)
PCI 0132:60:00.1#600000: EEH: not actionable (1,1,1)
EEH: Finished:'error_detected(permanent failure)'
With the change
EEH: Beginning: 'error_detected(permanent failure)'
EEH: Invoking lpfc->error_detected(permanent failure)
EEH: lpfc driver reports: 'disconnect'
EEH: Invoking lpfc->error_detected(permanent failure)
EEH: lpfc driver reports: 'disconnect'
EEH: Finished:'error_detected(permanent failure)'
To fix the issue, set channel state to permanent failure after
notifying the drivers.
Fixes: 38ddc01147 ("powerpc/eeh: Make permanently failed devices non-actionable")
Suggested-by: Mahesh Salgaonkar <mahesh@linux.ibm.com>
Signed-off-by: Ganesh Goudar <ganeshgr@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20230209105649.127707-1-ganeshgr@linux.ibm.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 10b34ece13 ]
The control flow of eeh_handle_normal_event() is a bit tricky.
Break out one of the error handling paths - rather than be in an else
block, we'll make it part of the regular body of the function and put a
'goto out;' in the true limb of the if.
Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211015070628.1331635-1-dja@axtens.net
Stable-dep-of: 9efcdaac36 ("powerpc/eeh: Set channel state after notifying the drivers")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 836b5b9fcc ]
Some RTAS functions that have work area parameters impose alignment
requirements on the work area passed to them by the OS. Examples
include:
- ibm,configure-connector
- ibm,update-nodes
- ibm,update-properties
4KB is the greatest alignment required by PAPR for such
buffers. rtas_data_buf used to have a __page_aligned attribute in the
arch/ppc64 days, but that was changed to __cacheline_aligned for
unknown reasons by commit 033ef338b6 ("powerpc: Merge rtas.c into
arch/powerpc/kernel"). That works out to 128-byte alignment
on ppc64, which isn't right.
This was found by inspection and I'm not aware of any real problems
caused by this. Either current RTAS implementations don't enforce the
alignment constraints, or rtas_data_buf is always being placed at a
4KB boundary by accident (or both, perhaps).
Use __aligned(SZ_4K) to ensure the rtas_data_buf has alignment
appropriate for all users.
Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
Fixes: 033ef338b6 ("powerpc: Merge rtas.c into arch/powerpc/kernel")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20230125-b4-powerpc-rtas-queue-v3-6-26929c8cce78@linux.ibm.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 9bce624384 ]
The first symbol exports of RTAS functions and data came with the (now
removed) scanlog driver in 2003:
https://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.git/commit/?id=f92e361842d5251e50562b09664082dcbd0548bb
At the time this was applied, EXPORT_SYMBOL_GPL() was very new, and
the exports of rtas_call() etc have remained non-GPL. As new APIs have
been added to the RTAS subsystem, their symbol exports have followed
the convention set by existing code.
However, the historical evidence is that RTAS function exports have been
added over time only to satisfy the needs of in-kernel users, and these
clients must have fairly intimate knowledge of how the APIs work to use
them safely. No out of tree users are known, and future ones seem
unlikely.
Arguably the default for RTAS symbols should have become
EXPORT_SYMBOL_GPL once it was available. Let's make it so now, and
exceptions can be evaluated as needed.
Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
Reviewed-by: Laurent Dufour <laurent.dufour@fr.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20230124140448.45938-3-nathanl@linux.ibm.com
Stable-dep-of: 836b5b9fcc ("powerpc/rtas: ensure 4KB alignment for rtas_data_buf")
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 0e25498f8c upstream.
There are two big uses of do_exit. The first is it's design use to be
the guts of the exit(2) system call. The second use is to terminate
a task after something catastrophic has happened like a NULL pointer
in kernel code.
Add a function make_task_dead that is initialy exactly the same as
do_exit to cover the cases where do_exit is called to handle
catastrophic failure. In time this can probably be reduced to just a
light wrapper around do_task_dead. For now keep it exactly the same so
that there will be no behavioral differences introducing this new
concept.
Replace all of the uses of do_exit that use it for catastraphic
task cleanup with make_task_dead to make it clear what the code
is doing.
As part of this rename rewind_stack_do_exit
rewind_stack_and_make_dead.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit ed2213bfb1 ]
rtas_os_term() is called during panic. Its behavior depends on a couple
of conditions in the /rtas node of the device tree, the traversal of
which entails locking and local IRQ state changes. If the kernel panics
while devtree_lock is held, rtas_os_term() as currently written could
hang.
Instead of discovering the relevant characteristics at panic time,
cache them in file-static variables at boot. Note the lookup for
"ibm,extended-os-term" is converted to of_property_read_bool() since it
is a boolean property, not an RTAS function token.
Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Andrew Donnellan <ajd@linux.ibm.com>
[mpe: Incorporate suggested change from Nick]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20221118150751.469393-4-nathanl@linux.ibm.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 0100e6bbdb ]
In the arch addition of PF_IO_WORKER, I missed parisc and powerpc for
some reason. Fix that up, ensuring they handle PF_IO_WORKER like they do
PF_KTHREAD in copy_thread().
Reported-by: Bruno Goncalves <bgoncalv@redhat.com>
Fixes: 4727dc20e0 ("arch: setup PF_IO_WORKER threads like PF_KTHREAD")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit c7acee3d2f upstream.
Christophe Leroy reported that commit 7b4537199a ("kbuild: link
symbol CRCs at final link, removing CONFIG_MODULE_REL_CRCS") broke
mpc85xx_defconfig + CONFIG_RELOCATABLE=y.
LD vmlinux
SYSMAP System.map
SORTTAB vmlinux
CHKREL vmlinux
WARNING: 451 bad relocations
c0b312a9 R_PPC_UADDR32 .head.text-0x3ff9ed54
c0b312ad R_PPC_UADDR32 .head.text-0x3ffac224
c0b312b1 R_PPC_UADDR32 .head.text-0x3ffb09f4
c0b312b5 R_PPC_UADDR32 .head.text-0x3fe184dc
c0b312b9 R_PPC_UADDR32 .head.text-0x3fe183a8
...
The compiler emits a bunch of R_PPC_UADDR32, which is not supported by
arch/powerpc/kernel/reloc_32.S.
The reason is there exists an unaligned symbol.
$ powerpc-linux-gnu-nm -n vmlinux
...
c0b31258 d spe_aligninfo
c0b31298 d __func__.0
c0b312a9 D sys_call_table
c0b319b8 d __func__.0
Commit 7b4537199a is not the root cause. Even before that, I can
reproduce the same issue for mpc85xx_defconfig + CONFIG_RELOCATABLE=y
+ CONFIG_MODVERSIONS=n.
It is just that nobody noticed because when CONFIG_MODVERSIONS is
enabled, a __crc_* symbol inserted before sys_call_table was hiding the
unalignment issue.
Adding alignment to the syscall table for ppc32 fixes the issue.
Cc: stable@vger.kernel.org
Reported-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Tested-by: Christophe Leroy <christophe.leroy@csgroup.eu>
[mpe: Trim change log discussion, add Cc stable]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/lkml/38605f6a-a568-f884-f06f-ea4da5b214f0@csgroup.eu/
Link: https://lore.kernel.org/r/20220820165129.1147589-1-masahiroy@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit ca829e05d3 ]
On 64-bit, calling jump_label_init() in setup_feature_keys() is too
late because static keys may be used in subroutines of
parse_early_param() which is again subroutine of early_init_devtree().
For example booting with "threadirqs":
static_key_enable_cpuslocked(): static key '0xc000000002953260' used before call to jump_label_init()
WARNING: CPU: 0 PID: 0 at kernel/jump_label.c:166 static_key_enable_cpuslocked+0xfc/0x120
...
NIP static_key_enable_cpuslocked+0xfc/0x120
LR static_key_enable_cpuslocked+0xf8/0x120
Call Trace:
static_key_enable_cpuslocked+0xf8/0x120 (unreliable)
static_key_enable+0x30/0x50
setup_forced_irqthreads+0x28/0x40
do_early_param+0xa0/0x108
parse_args+0x290/0x4e0
parse_early_options+0x48/0x5c
parse_early_param+0x58/0x84
early_init_devtree+0xd4/0x518
early_setup+0xb4/0x214
So call jump_label_init() just before parse_early_param() in
early_init_devtree().
Suggested-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Zhouyi Zhou <zhouzhouyi@gmail.com>
[mpe: Add call trace to change log and minor wording edits.]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220726015747.11754-1-zhouzhouyi@gmail.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 8d48562a27 upstream.
The recent change to get_phb_number() causes a DEBUG_ATOMIC_SLEEP
warning on some systems:
BUG: sleeping function called from invalid context at kernel/locking/mutex.c:580
in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 1, name: swapper
preempt_count: 1, expected: 0
RCU nest depth: 0, expected: 0
1 lock held by swapper/1:
#0: c157efb0 (hose_spinlock){+.+.}-{2:2}, at: pcibios_alloc_controller+0x64/0x220
Preemption disabled at:
[<00000000>] 0x0
CPU: 0 PID: 1 Comm: swapper Not tainted 5.19.0-yocto-standard+ #1
Call Trace:
[d101dc90] [c073b264] dump_stack_lvl+0x50/0x8c (unreliable)
[d101dcb0] [c0093b70] __might_resched+0x258/0x2a8
[d101dcd0] [c0d3e634] __mutex_lock+0x6c/0x6ec
[d101dd50] [c0a84174] of_alias_get_id+0x50/0xf4
[d101dd80] [c002ec78] pcibios_alloc_controller+0x1b8/0x220
[d101ddd0] [c140c9dc] pmac_pci_init+0x198/0x784
[d101de50] [c140852c] discover_phbs+0x30/0x4c
[d101de60] [c0007fd4] do_one_initcall+0x94/0x344
[d101ded0] [c1403b40] kernel_init_freeable+0x1a8/0x22c
[d101df10] [c00086e0] kernel_init+0x34/0x160
[d101df30] [c001b334] ret_from_kernel_thread+0x5c/0x64
This is because pcibios_alloc_controller() holds hose_spinlock but
of_alias_get_id() takes of_mutex which can sleep.
The hose_spinlock protects the phb_bitmap, and also the hose_list, but
it doesn't need to be held while get_phb_number() calls the OF routines,
because those are only looking up information in the device tree.
So fix it by having get_phb_number() take the hose_spinlock itself, only
where required, and then dropping the lock before returning.
pcibios_alloc_controller() then needs to take the lock again before the
list_add() but that's safe, the order of the list is not important.
Fixes: 0fe1e96fef ("powerpc/pci: Prefer PCI domain assignment via DT 'linux,pci-domain' and alias")
Reported-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220815065550.1303620-1-mpe@ellerman.id.au
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit f4b39e88b4 ]
The recent change to the PHB numbering logic has a logic error in the
handling of "ibm,opal-phbid".
When an "ibm,opal-phbid" property is present, &prop is written to and
ret is set to zero.
The following call to of_alias_get_id() is skipped because ret == 0.
But then the if (ret >= 0) is true, and the body of that if statement
sets prop = ret which throws away the value that was just read from
"ibm,opal-phbid".
Fix the logic by only doing the ret >= 0 check in the of_alias_get_id()
case.
Fixes: 0fe1e96fef ("powerpc/pci: Prefer PCI domain assignment via DT 'linux,pci-domain' and alias")
Reviewed-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220802105723.1055178-1-mpe@ellerman.id.au
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 0fe1e96fef ]
Other Linux architectures use DT property 'linux,pci-domain' for
specifying fixed PCI domain of PCI controller specified in Device-Tree.
And lot of Freescale powerpc boards have defined numbered pci alias in
Device-Tree for every PCIe controller which number specify preferred PCI
domain.
So prefer usage of DT property 'linux,pci-domain' (via function
of_get_pci_domain_nr()) and DT pci alias (via function
of_alias_get_id()) on powerpc architecture for assigning PCI domain to
PCI controller.
Fixes: 63a72284b1 ("powerpc/pci: Assign fixed PHB number based on device-tree properties")
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220706102148.5060-2-pali@kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit be640317a1 ]
With GCC 12 allmodconfig prom_init fails to build:
Error: External symbol 'memset' referenced from prom_init.c
make[2]: *** [arch/powerpc/kernel/Makefile:204: arch/powerpc/kernel/prom_init_check] Error 1
The allmodconfig build enables KASAN, so all calls to memset in
prom_init should be converted to __memset by the #ifdefs in
asm/string.h, because prom_init must use the non-KASAN instrumented
versions.
The build failure happens because there's a call to memset that hasn't
been caught by the pre-processor and converted to __memset. Typically
that's because it's a memset generated by the compiler itself, and that
is the case here.
With GCC 12, allmodconfig enables CONFIG_INIT_STACK_ALL_PATTERN, which
causes the compiler to emit memset calls to initialise on-stack
variables with a pattern.
Because prom_init is non-user-facing boot-time only code, as a
workaround just disable stack variable initialisation to unbreak the
build.
Reported-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220718134418.354114-1-mpe@ellerman.id.au
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 7bc08056a6 upstream.
Add a special case to block_rtas_call() to allow the ibm,platform-dump RTAS
call through the RTAS filter if the buffer address is 0.
According to PAPR, ibm,platform-dump is called with a null buffer address
to notify the platform firmware that processing of a particular dump is
finished.
Without this, on a pseries machine with CONFIG_PPC_RTAS_FILTER enabled, an
application such as rtas_errd that is attempting to retrieve a dump will
encounter an error at the end of the retrieval process.
Fixes: bd59380c5b ("powerpc/rtas: Restrict RTAS requests from userspace")
Cc: stable@vger.kernel.org
Reported-by: Sathvika Vasireddy <sathvika@linux.ibm.com>
Signed-off-by: Andrew Donnellan <ajd@linux.ibm.com>
Reviewed-by: Tyrel Datwyler <tyreld@linux.ibm.com>
Reviewed-by: Nathan Lynch <nathanl@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220614134952.156010-1-ajd@linux.ibm.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit a1b29ba2f2 ]
The following KASAN warning was reported in our kernel.
BUG: KASAN: stack-out-of-bounds in get_wchan+0x188/0x250
Read of size 4 at addr d216f958 by task ps/14437
CPU: 3 PID: 14437 Comm: ps Tainted: G O 5.10.0 #1
Call Trace:
[daa63858] [c0654348] dump_stack+0x9c/0xe4 (unreliable)
[daa63888] [c035cf0c] print_address_description.constprop.3+0x8c/0x570
[daa63908] [c035d6bc] kasan_report+0x1ac/0x218
[daa63948] [c00496e8] get_wchan+0x188/0x250
[daa63978] [c0461ec8] do_task_stat+0xce8/0xe60
[daa63b98] [c0455ac8] proc_single_show+0x98/0x170
[daa63bc8] [c03cab8c] seq_read_iter+0x1ec/0x900
[daa63c38] [c03cb47c] seq_read+0x1dc/0x290
[daa63d68] [c037fc94] vfs_read+0x164/0x510
[daa63ea8] [c03808e4] ksys_read+0x144/0x1d0
[daa63f38] [c005b1dc] ret_from_syscall+0x0/0x38
--- interrupt: c00 at 0x8fa8f4
LR = 0x8fa8cc
The buggy address belongs to the page:
page:98ebcdd2 refcount:0 mapcount:0 mapping:00000000 index:0x2 pfn:0x1216f
flags: 0x0()
raw: 00000000 00000000 01010122 00000000 00000002 00000000 ffffffff 00000000
raw: 00000000
page dumped because: kasan: bad access detected
Memory state around the buggy address:
d216f800: 00 00 00 00 00 f1 f1 f1 f1 00 00 00 00 00 00 00
d216f880: f2 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>d216f900: 00 00 00 00 00 00 00 00 00 00 00 f1 f1 f1 f1 00
^
d216f980: f2 f2 f2 f2 f2 f2 f2 00 00 00 00 00 00 00 00 00
d216fa00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
After looking into this issue, I find the buggy address belongs
to the task stack region. It seems KASAN has something wrong.
I look into the code of __get_wchan in x86 architecture and
find the same issue has been resolved by the commit
f7d27c35dd ("x86/mm, kasan: Silence KASAN warnings in get_wchan()").
The solution could be applied to powerpc architecture too.
As Andrey Ryabinin said, get_wchan() is racy by design, it may
access volatile stack of running task, thus it may access
redzone in a stack frame and cause KASAN to warn about this.
Use READ_ONCE_NOCHECK() to silence these warnings.
Reported-by: Wanming Hu <huwanming@huaweil.com>
Signed-off-by: He Ying <heying24@huawei.com>
Signed-off-by: Chen Jingwen <chenjingwen6@huawei.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220121014418.155675-1-heying24@huawei.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit d51f86cfd8 upstream.
The dssall ("Data Stream Stop All") instruction is obsolete altogether
with other Data Cache Instructions since ISA 2.03 (year 2006).
LLVM IAS does not support it but PPC970 seems to be using it.
This switches dssall to .long as there is no much point in fixing LLVM.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211221055904.555763-6-aik@ozlabs.ru
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 8e12784444 upstream.
The ptrace PEEKUSR/POKEUSR (aka PEEKUSER/POKEUSER) API allows a process
to read/write registers of another process.
To get/set a register, the API takes an index into an imaginary address
space called the "USER area", where the registers of the process are
laid out in some fashion.
The kernel then maps that index to a particular register in its own data
structures and gets/sets the value.
The API only allows a single machine-word to be read/written at a time.
So 4 bytes on 32-bit kernels and 8 bytes on 64-bit kernels.
The way floating point registers (FPRs) are addressed is somewhat
complicated, because double precision float values are 64-bit even on
32-bit CPUs. That means on 32-bit kernels each FPR occupies two
word-sized locations in the USER area. On 64-bit kernels each FPR
occupies one word-sized location in the USER area.
Internally the kernel stores the FPRs in an array of u64s, or if VSX is
enabled, an array of pairs of u64s where one half of each pair stores
the FPR. Which half of the pair stores the FPR depends on the kernel's
endianness.
To handle the different layouts of the FPRs depending on VSX/no-VSX and
big/little endian, the TS_FPR() macro was introduced.
Unfortunately the TS_FPR() macro does not take into account the fact
that the addressing of each FPR differs between 32-bit and 64-bit
kernels. It just takes the index into the "USER area" passed from
userspace and indexes into the fp_state.fpr array.
On 32-bit there are 64 indexes that address FPRs, but only 32 entries in
the fp_state.fpr array, meaning the user can read/write 256 bytes past
the end of the array. Because the fp_state sits in the middle of the
thread_struct there are various fields than can be overwritten,
including some pointers. As such it may be exploitable.
It has also been observed to cause systems to hang or otherwise
misbehave when using gdbserver, and is probably the root cause of this
report which could not be easily reproduced:
https://lore.kernel.org/linuxppc-dev/dc38afe9-6b78-f3f5-666b-986939e40fc6@keymile.com/
Rather than trying to make the TS_FPR() macro even more complicated to
fix the bug, or add more macros, instead add a special-case for 32-bit
kernels. This is more obvious and hopefully avoids a similar bug
happening again in future.
Note that because 32-bit kernels never have VSX enabled the code doesn't
need to consider TS_FPRWIDTH/OFFSET at all. Add a BUILD_BUG_ON() to
ensure that 32-bit && VSX is never enabled.
Fixes: 87fec0514f ("powerpc: PTRACE_PEEKUSR/PTRACE_POKEUSER of FPR registers in little endian builds")
Cc: stable@vger.kernel.org # v3.13+
Reported-by: Ariel Miculas <ariel.miculas@belden.com>
Tested-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220609133245.573565-1-mpe@ellerman.id.au
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit b793a01000 ]
__setup() handlers should return 1 to obsolete_checksetup() in
init/main.c to indicate that the boot option has been handled.
A return of 0 causes the boot option/value to be listed as an Unknown
kernel parameter and added to init's (limited) argument or environment
strings.
Also, error return codes don't mean anything to obsolete_checksetup() --
only non-zero (usually 1) or zero. So return 1 from powersave_off().
Fixes: 302eca184f ("[POWERPC] cell: use ppc_md->power_save instead of cbe_idle_loop")
Reported-by: Igor Zhbanov <izh1979@gmail.com>
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220502192925.19954-1-rdunlap@infradead.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 15eb77f873 ]
Boot memory area is setup as separate PT_LOAD segment in the vmcore
as it is moved by f/w, on crash, to a destination address provided by
the kernel. Having separate PT_LOAD segment helps in handling the
different physical address and offset for boot memory area in the
vmcore.
Commit ced1bf52f4 ("powerpc/fadump: merge adjacent memory ranges to
reduce PT_LOAD segements") inadvertly broke this pre-condition for
cases where some of the first kernel memory is available adjacent to
boot memory area. This scenario is rare but possible when memory for
fadump could not be reserved adjacent to boot memory area owing to
memory hole or such. Reading memory from a vmcore exported in such
scenario provides incorrect data. Fix it by ensuring no other region
is folded into boot memory area.
Fixes: ced1bf52f4 ("powerpc/fadump: merge adjacent memory ranges to reduce PT_LOAD segements")
Signed-off-by: Hari Bathini <hbathini@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220406093839.206608-2-hbathini@linux.ibm.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 7c5ed82b80 ]
On large config LPARs (having 192 and more cores), Linux fails to boot
due to insufficient memory in the first memblock. It is due to the
memory reservation for the crash kernel which starts at 128MB offset of
the first memblock. This memory reservation for the crash kernel doesn't
leave enough space in the first memblock to accommodate other essential
system resources.
The crash kernel start address was set to 128MB offset by default to
ensure that the crash kernel get some memory below the RMA region which
is used to be of size 256MB. But given that the RMA region size can be
512MB or more, setting the crash kernel offset to mid of RMA size will
leave enough space for the kernel to allocate memory for other system
resources.
Since the above crash kernel offset change is only applicable to the LPAR
platform, the LPAR feature detection is pushed before the crash kernel
reservation. The rest of LPAR specific initialization will still
be done during pseries_probe_fw_features as usual.
This patch is dependent on changes to paca allocation for boot CPU. It
expect boot CPU to discover 1T segment support which is introduced by
the patch posted here:
https://lists.ozlabs.org/pipermail/linuxppc-dev/2022-January/239175.html
Reported-by: Abdul haleem <abdhalee@linux.vnet.ibm.com>
Signed-off-by: Sourabh Jain <sourabhjain@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220204085601.107257-1-sourabhjain@linux.ibm.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 06e629c25d ]
In panic path, fadump is triggered via a panic notifier function.
Before calling panic notifier functions, smp_send_stop() gets called,
which stops all CPUs except the panic'ing CPU. Commit 8389b37dff
("powerpc: stop_this_cpu: remove the cpu from the online map.") and
again commit bab26238bb ("powerpc: Offline CPU in stop_this_cpu()")
started marking CPUs as offline while stopping them. So, if a kernel
has either of the above commits, vmcore captured with fadump via panic
path would not process register data for all CPUs except the panic'ing
CPU. Sample output of crash-utility with such vmcore:
# crash vmlinux vmcore
...
KERNEL: vmlinux
DUMPFILE: vmcore [PARTIAL DUMP]
CPUS: 1
DATE: Wed Nov 10 09:56:34 EST 2021
UPTIME: 00:00:42
LOAD AVERAGE: 2.27, 0.69, 0.24
TASKS: 183
NODENAME: XXXXXXXXX
RELEASE: 5.15.0+
VERSION: #974 SMP Wed Nov 10 04:18:19 CST 2021
MACHINE: ppc64le (2500 Mhz)
MEMORY: 8 GB
PANIC: "Kernel panic - not syncing: sysrq triggered crash"
PID: 3394
COMMAND: "bash"
TASK: c0000000150a5f80 [THREAD_INFO: c0000000150a5f80]
CPU: 1
STATE: TASK_RUNNING (PANIC)
crash> p -x __cpu_online_mask
__cpu_online_mask = $1 = {
bits = {0x2, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0}
}
crash>
crash>
crash> p -x __cpu_active_mask
__cpu_active_mask = $2 = {
bits = {0xff, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0}
}
crash>
While this has been the case since fadump was introduced, the issue
was not identified for two probable reasons:
- In general, the bulk of the vmcores analyzed were from crash
due to exception.
- The above did change since commit 8341f2f222 ("sysrq: Use
panic() to force a crash") started using panic() instead of
deferencing NULL pointer to force a kernel crash. But then
commit de6e5d3841 ("powerpc: smp_send_stop do not offline
stopped CPUs") stopped marking CPUs as offline till kernel
commit bab26238bb ("powerpc: Offline CPU in stop_this_cpu()")
reverted that change.
To ensure post processing register data of all other CPUs happens
as intended, let panic() function take the crash friendly path (read
crash_smp_send_stop()) with the help of crash_kexec_post_notifiers
option. Also, as register data for all CPUs is captured by f/w, skip
IPI callbacks here for fadump, to avoid any complications in finding
the right backtraces.
Signed-off-by: Hari Bathini <hbathini@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211207103719.91117-2-hbathini@linux.ibm.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 219572d2fc ]
Kdump can be triggered after panic_notifers since commit f06e5153f4
("kernel/panic.c: add "crash_kexec_post_notifiers" option for kdump
after panic_notifers") introduced crash_kexec_post_notifiers option.
But using this option would mean smp_send_stop(), that marks all other
CPUs as offline, gets called before kdump is triggered. As a result,
kdump routines fail to save other CPUs' registers. To fix this, kdump
friendly crash_smp_send_stop() function was introduced with kernel
commit 0ee59413c9 ("x86/panic: replace smp_send_stop() with kdump
friendly version in panic path"). Override this kdump friendly weak
function to handle crash_kexec_post_notifiers option appropriately
on powerpc.
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Hari Bathini <hbathini@linux.ibm.com>
[Fixed signature of crash_stop_this_cpu() - reported by lkp@intel.com]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211207103719.91117-1-hbathini@linux.ibm.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 5dad4ba68a ]
It is possible for all CPUs to miss the pending cpumask becoming clear,
and then nobody resetting it, which will cause the lockup detector to
stop working. It will eventually expire, but watchdog_smp_panic will
avoid doing anything if the pending mask is clear and it will never be
reset.
Order the cpumask clear vs the subsequent test to close this race.
Add an extra check for an empty pending mask when the watchdog fires and
finds its bit still clear, to try to catch any other possible races or
bugs here and keep the watchdog working. The extra test in
arch_touch_nmi_watchdog is required to prevent the new warning from
firing off.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Laurent Dufour <ldufour@linux.ibm.com>
Debugged-by: Laurent Dufour <ldufour@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211110025056.2084347-2-npiggin@gmail.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 91668ab7db ]
PowerISA v3.1 introduces new control bit (PMCCEXT) for restricting
access to group B PMU registers in problem state when
MMCR0 PMCC=0b00. In problem state and when MMCR0 PMCC=0b00,
setting the Monitor Mode Control Register bit 54 (MMCR0 PMCCEXT),
will restrict read permission on Group B Performance Monitor
Registers (SIER, SIAR, SDAR and MMCR1). When this bit is set to zero,
group B registers will be readable. In other platforms (like power9),
the older behaviour is retained where group B PMU SPRs are readable.
Patch adds support for MMCR0 PMCCEXT bit in power10 by enabling
this bit during boot and during the PMU event enable/disable callback
functions.
Signed-off-by: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1606409684-1589-8-git-send-email-atrajeev@linux.vnet.ibm.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 344fbab991 ]
The only thing keeping the cpu_setup() and cpu_restore() functions
used in the cputable entries for Power7, Power8, Power9 and Power10 in
assembly was cpu_restore() being called before there was a stack in
generic_secondary_smp_init(). Commit ("powerpc/64: Set up a kernel
stack for secondaries before cpu_restore()") means that it is now
possible to use C.
Rewrite the functions in C so they are a little bit easier to read.
This is not changing their functionality.
Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
[mpe: Tweak copyright and authorship notes]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20201014072837.24539-2-jniethe5@gmail.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 1e35eba405 upstream.
As spotted and explained in commit c12ab8dbc4 ("powerpc/8xx: Fix
Oops with STRICT_KERNEL_RWX without DEBUG_RODATA_TEST"), the selection
of STRICT_KERNEL_RWX without selecting DEBUG_RODATA_TEST has spotted
the lack of the DIRTY bit in the pinned kernel data TLBs.
This problem should have been detected a lot earlier if things had
been working as expected. But due to an incredible level of chance or
mishap, this went undetected because of a set of bugs: In fact the
DTLBs were not pinned, because instead of setting the reserve bit
in MD_CTR, it was set in MI_CTR that is the register for ITLBs.
But then, another huge bug was there: the physical address was
reset to 0 at the boundary between RO and RW areas, leading to the
same physical space being mapped at both 0xc0000000 and 0xc8000000.
This had by miracle no consequence until now because the entry was
not really pinned so it was overwritten soon enough to go undetected.
Of course, now that we really pin the DTLBs, it must be fixed as well.
Fixes: f76c8f6d25 ("powerpc/8xx: Add function to set pinned TLBs")
Cc: stable@vger.kernel.org # v5.8+
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Depends-on: c12ab8dbc4 ("powerpc/8xx: Fix Oops with STRICT_KERNEL_RWX without DEBUG_RODATA_TEST")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/a21e9a057fe2d247a535aff0d157a54eefee017a.1636963688.git.christophe.leroy@csgroup.eu
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Nathan Lynch
Aneesh Kumar K.V
Jens Axboe
Michael Ellerman
Rohan McLure
Ganesh Goudar
Daniel Axtens
Eric W. Biederman
Liang He
Masahiro Yamada
Zhouyi Zhou
Pali Rohár
Liam Howlett
Naveen N. Rao
Andrew Donnellan
He Ying
Alexey Kardashevskiy
Randy Dunlap
Hari Bathini
Hangyu Hua
Sourabh Jain
Andreas Gruenbacher
Christophe Leroy
Nicholas Piggin
Julia Lawall
Athira Rajeev
Jordan Niethe
Peiwei Hu