[ Upstream commit a26c4dbb3d9c1821cb0fc11cb2dbc32d5bf3463b ]
These functions are not used outside of sstep.c
Fixes: 350779a29f11 ("powerpc: Handle most loads and stores in instruction emulation code")
Signed-off-by: Michal Suchanek <msuchanek@suse.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://patch.msgid.link/20241001130356.14664-1-msuchanek@suse.de
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 0161bd38c24312853ed5ae9a425a1c41c4ac674a ]
On powerpc64 as shown below by readelf, vDSO functions symbols have
type NOTYPE.
$ powerpc64-linux-gnu-readelf -a arch/powerpc/kernel/vdso/vdso64.so.dbg
ELF Header:
Magic: 7f 45 4c 46 02 02 01 00 00 00 00 00 00 00 00 00
Class: ELF64
Data: 2's complement, big endian
Version: 1 (current)
OS/ABI: UNIX - System V
ABI Version: 0
Type: DYN (Shared object file)
Machine: PowerPC64
Version: 0x1
...
Symbol table '.dynsym' contains 12 entries:
Num: Value Size Type Bind Vis Ndx Name
...
1: 0000000000000524 84 NOTYPE GLOBAL DEFAULT 8 __[...]@@LINUX_2.6.15
...
4: 0000000000000000 0 OBJECT GLOBAL DEFAULT ABS LINUX_2.6.15
5: 00000000000006c0 48 NOTYPE GLOBAL DEFAULT 8 __[...]@@LINUX_2.6.15
Symbol table '.symtab' contains 56 entries:
Num: Value Size Type Bind Vis Ndx Name
...
45: 0000000000000000 0 OBJECT GLOBAL DEFAULT ABS LINUX_2.6.15
46: 00000000000006c0 48 NOTYPE GLOBAL DEFAULT 8 __kernel_getcpu
47: 0000000000000524 84 NOTYPE GLOBAL DEFAULT 8 __kernel_clock_getres
To overcome that, commit ba83b3239e65 ("selftests: vDSO: fix vDSO
symbols lookup for powerpc64") was applied to have selftests also
look for NOTYPE symbols, but the correct fix should be to flag VDSO
entry points as functions.
The original commit that brought VDSO support into powerpc/64 has the
following explanation:
Note that the symbols exposed by the vDSO aren't "normal" function symbols, apps
can't be expected to link against them directly, the vDSO's are both seen
as if they were linked at 0 and the symbols just contain offsets to the
various functions. This is done on purpose to avoid a relocation step
(ppc64 functions normally have descriptors with abs addresses in them).
When glibc uses those functions, it's expected to use it's own trampolines
that know how to reach them.
The descriptors it's talking about are the OPD function descriptors
used on ABI v1 (big endian). But it would be more correct for a text
symbol to have type function, even if there's no function descriptor
for it.
glibc has a special case already for handling the VDSO symbols which
creates a fake opd pointing at the kernel symbol. So changing the VDSO
symbol type to function shouldn't affect that.
For ABI v2, there is no function descriptors and VDSO functions can
safely have function type.
So lets flag VDSO entry points as functions and revert the
selftest change.
Link: 5f2dd691b6
Fixes: ba83b3239e65 ("selftests: vDSO: fix vDSO symbols lookup for powerpc64")
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Reviewed-By: Segher Boessenkool <segher@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://patch.msgid.link/b6ad2f1ee9887af3ca5ecade2a56f4acda517a85.1728512263.git.christophe.leroy@csgroup.eu
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 0db880fc865ffb522141ced4bfa66c12ab1fbb70 upstream.
nmi_enter()/nmi_exit() touches per cpu variables which can lead to kernel
crash when invoked during real mode interrupt handling (e.g. early HMI/MCE
interrupt handler) if percpu allocation comes from vmalloc area.
Early HMI/MCE handlers are called through DEFINE_INTERRUPT_HANDLER_NMI()
wrapper which invokes nmi_enter/nmi_exit calls. We don't see any issue when
percpu allocation is from the embedded first chunk. However with
CONFIG_NEED_PER_CPU_PAGE_FIRST_CHUNK enabled there are chances where percpu
allocation can come from the vmalloc area.
With kernel command line "percpu_alloc=page" we can force percpu allocation
to come from vmalloc area and can see kernel crash in machine_check_early:
[ 1.215714] NIP [c000000000e49eb4] rcu_nmi_enter+0x24/0x110
[ 1.215717] LR [c0000000000461a0] machine_check_early+0xf0/0x2c0
[ 1.215719] --- interrupt: 200
[ 1.215720] [c000000fffd73180] [0000000000000000] 0x0 (unreliable)
[ 1.215722] [c000000fffd731b0] [0000000000000000] 0x0
[ 1.215724] [c000000fffd73210] [c000000000008364] machine_check_early_common+0x134/0x1f8
Fix this by avoiding use of nmi_enter()/nmi_exit() in real mode if percpu
first chunk is not embedded.
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Tested-by: Shirisha Ganta <shirisha@linux.ibm.com>
Signed-off-by: Mahesh Salgaonkar <mahesh@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240410043006.81577-1-mahesh@linux.ibm.com
[ Conflicts in arch/powerpc/include/asm/interrupt.h
because machine_check_early() and machine_check_exception()
has been refactored. ]
Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit be140f1732b523947425aaafbe2e37b41b622d96 ]
There is code that builds with calls to IO accessors even when
CONFIG_PCI=n, but the actual calls are guarded by runtime checks.
If not those calls would be faulting, because the page at virtual
address zero is (usually) not mapped into the kernel. As Arnd pointed
out, it is possible a large port value could cause the address to be
above mmap_min_addr which would then access userspace, which would be
a bug.
To avoid any such issues, set _IO_BASE to POISON_POINTER_DELTA. That
is a value chosen to point into unmapped space between the kernel and
userspace, so any access will always fault.
Note that on 32-bit POISON_POINTER_DELTA is 0, so the patch only has an
effect on 64-bit.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240503075619.394467-2-mpe@ellerman.id.au
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 03c0f2c2b2220fc9cf8785cd7b61d3e71e24a366 ]
With -Wextra clang warns about pointer arithmetic using a null pointer.
When building with CONFIG_PCI=n, that triggers a warning in the IO
accessors, eg:
In file included from linux/arch/powerpc/include/asm/io.h:672:
linux/arch/powerpc/include/asm/io-defs.h:23:1: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
23 | DEF_PCI_AC_RET(inb, u8, (unsigned long port), (port), pio, port)
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
...
linux/arch/powerpc/include/asm/io.h:591:53: note: expanded from macro '__do_inb'
591 | #define __do_inb(port) readb((PCI_IO_ADDR)_IO_BASE + port);
| ~~~~~~~~~~~~~~~~~~~~~ ^
That is because when CONFIG_PCI=n, _IO_BASE is defined as 0.
Although _IO_BASE is defined as plain 0, the cast (PCI_IO_ADDR) converts
it to void * before the addition with port happens.
Instead the addition can be done first, and then the cast. The resulting
value will be the same, but avoids the warning, and also avoids void
pointer arithmetic which is apparently non-standard.
Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Closes: https://lore.kernel.org/all/CA+G9fYtEh8zmq8k8wE-8RZwW-Qr927RLTn+KqGnq1F=ptaaNsA@mail.gmail.com
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240503075619.394467-1-mpe@ellerman.id.au
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit ff2e185cf73df480ec69675936c4ee75a445c3e4 ]
plpar_hcall(), plpar_hcall9(), and related functions expect callers to
provide valid result buffers of certain minimum size. Currently this
is communicated only through comments in the code and the compiler has
no idea.
For example, if I write a bug like this:
long retbuf[PLPAR_HCALL_BUFSIZE]; // should be PLPAR_HCALL9_BUFSIZE
plpar_hcall9(H_ALLOCATE_VAS_WINDOW, retbuf, ...);
This compiles with no diagnostics emitted, but likely results in stack
corruption at runtime when plpar_hcall9() stores results past the end
of the array. (To be clear this is a contrived example and I have not
found a real instance yet.)
To make this class of error less likely, we can use explicitly-sized
array parameters instead of pointers in the declarations for the hcall
APIs. When compiled with -Warray-bounds[1], the code above now
provokes a diagnostic like this:
error: array argument is too small;
is of size 32, callee requires at least 72 [-Werror,-Warray-bounds]
60 | plpar_hcall9(H_ALLOCATE_VAS_WINDOW, retbuf,
| ^ ~~~~~~
[1] Enabled for LLVM builds but not GCC for now. See commit
0da6e5fd6c37 ("gcc: disable '-Warray-bounds' for gcc-13 too") and
related changes.
Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240408-pseries-hvcall-retbuf-v1-1-ebc73d7253cf@linux.ibm.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 2d43cc701b96f910f50915ac4c2a0cae5deb734c upstream.
Building ppc64le_defconfig with GCC 14 fails with assembler errors:
CC fs/readdir.o
/tmp/ccdQn0mD.s: Assembler messages:
/tmp/ccdQn0mD.s:212: Error: operand out of domain (18 is not a multiple of 4)
/tmp/ccdQn0mD.s:226: Error: operand out of domain (18 is not a multiple of 4)
... [6 lines]
/tmp/ccdQn0mD.s:1699: Error: operand out of domain (18 is not a multiple of 4)
A snippet of the asm shows:
# ../fs/readdir.c:210: unsafe_copy_dirent_name(dirent->d_name, name, namlen, efault_end);
ld 9,0(29) # MEM[(u64 *)name_38(D) + _88 * 1], MEM[(u64 *)name_38(D) + _88 * 1]
# 210 "../fs/readdir.c" 1
1: std 9,18(8) # put_user # *__pus_addr_52, MEM[(u64 *)name_38(D) + _88 * 1]
The 'std' instruction requires a 4-byte aligned displacement because
it is a DS-form instruction, and as the assembler says, 18 is not a
multiple of 4.
A similar error is seen with GCC 13 and CONFIG_UBSAN_SIGNED_WRAP=y.
The fix is to change the constraint on the memory operand to put_user(),
from "m" which is a general memory reference to "YZ".
The "Z" constraint is documented in the GCC manual PowerPC machine
constraints, and specifies a "memory operand accessed with indexed or
indirect addressing". "Y" is not documented in the manual but specifies
a "memory operand for a DS-form instruction". Using both allows the
compiler to generate a DS-form "std" or X-form "stdx" as appropriate.
The change has to be conditional on CONFIG_PPC_KERNEL_PREFIXED because
the "Y" constraint does not guarantee 4-byte alignment when prefixed
instructions are enabled.
Unfortunately clang doesn't support the "Y" constraint so that has to be
behind an ifdef.
Although the build error is only seen with GCC 13/14, that appears
to just be luck. The constraint has been incorrect since it was first
added.
Fixes: c20beffeec3c ("powerpc/uaccess: Use flexible addressing with __put_user()/__get_user()")
Cc: stable@vger.kernel.org # v5.10+
Suggested-by: Kewen Lin <linkw@gcc.gnu.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240529123029.146953-1-mpe@ellerman.id.au
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 6d4341638516bf97b9a34947e0bd95035a8230a5 ]
Couple of Minor fixes:
- hcall return values are long. Fix that for h_get_mpp, h_get_ppp and
parse_ppp_data
- If hcall fails, values set should be at-least zero. It shouldn't be
uninitialized values. Fix that for h_get_mpp and h_get_ppp
Signed-off-by: Shrikanth Hegde <sshegde@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240412092047.455483-3-sshegde@linux.ibm.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 5f491356b7149564ab22323ccce79c8d595bfd0c ]
Binutils 2.38 complains about the use of mfpmr when building
ppc6xx_defconfig:
CC arch/powerpc/kernel/pmc.o
{standard input}: Assembler messages:
{standard input}:45: Error: unrecognized opcode: `mfpmr'
{standard input}:56: Error: unrecognized opcode: `mtpmr'
This is because by default the kernel is built with -mcpu=powerpc, and
the mt/mfpmr instructions are not defined.
It can be avoided by enabling CONFIG_E300C3_CPU, but just adding that to
the defconfig will leave open the possibility of randconfig failures.
So add machine directives around the mt/mfpmr instructions to tell
binutils how to assemble them.
Cc: stable@vger.kernel.org
Reported-by: Jan-Benedict Glaw <jbglaw@lug-owl.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240229122521.762431-3-mpe@ellerman.id.au
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit d8c3f243d4db24675b653f0568bb65dae34e6455 ]
With NUMA=n and FA_DUMP=y or PRESERVE_FA_DUMP=y the build fails with:
arch/powerpc/kernel/fadump.c:1739:22: error: no previous prototype for ‘arch_reserved_kernel_pages’ [-Werror=missing-prototypes]
1739 | unsigned long __init arch_reserved_kernel_pages(void)
| ^~~~~~~~~~~~~~~~~~~~~~~~~~
The prototype for arch_reserved_kernel_pages() is in include/linux/mm.h,
but it's guarded by __HAVE_ARCH_RESERVED_KERNEL_PAGES. The powerpc
headers define __HAVE_ARCH_RESERVED_KERNEL_PAGES in asm/mmzone.h, which
is not included into the generic headers when NUMA=n.
Move the definition of __HAVE_ARCH_RESERVED_KERNEL_PAGES into asm/mmu.h
which is included regardless of NUMA=n.
Additionally the ifdef around __HAVE_ARCH_RESERVED_KERNEL_PAGES needs to
also check for CONFIG_PRESERVE_FA_DUMP.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20231130114433.3053544-1-mpe@ellerman.id.au
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 09ca497528dac12cbbceab8197011c875a96d053 ]
Last user of in_kernel_text() stopped using in with
commit 549e8152de80 ("powerpc: Make the 64-bit kernel as a
position-independent executable").
Generic function is_kernel_text() does the same.
So remote it.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/2a3a5b6f8cc0ef4e854d7b764f66aa8d2ee270d2.1624813698.git.christophe.leroy@csgroup.eu
Stable-dep-of: 1b1e38002648 ("powerpc: add crtsavres.o to always-y instead of extra-y")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit cc8ee288f484a2a59c01ccd4d8a417d6ed3466e3 ]
40x TLB handlers were reworked by commit 2c74e2586bb9 ("powerpc/40x:
Rework 40x PTE access and TLB miss") to not require PTE_ATOMIC_UPDATES
anymore.
Then commit 4e1df545e2fa ("powerpc/pgtable: Drop PTE_ATOMIC_UPDATES")
removed all code related to PTE_ATOMIC_UPDATES.
Remove left over PTE_ATOMIC_UPDATES macro.
Fixes: 2c74e2586bb9 ("powerpc/40x: Rework 40x PTE access and TLB miss")
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/f061db5857fcd748f84a6707aad01754686ce97e.1695659959.git.christophe.leroy@csgroup.eu
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 5d9cea8a552ee122e21fbd5a3c5d4eb85f648e06 ]
On 8xx, PAGE_NONE is handled by setting _PAGE_NA instead of clearing
_PAGE_USER.
But then pte_user() returns 1 also for PAGE_NONE.
As _PAGE_NA prevent reads, add a specific version of pte_read()
that returns 0 when _PAGE_NA is set instead of always returning 1.
Fixes: 351750331fc1 ("powerpc/mm: Introduce _PAGE_NA")
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/57bcfbe578e43123f9ed73e040229b80f1ad56ec.1695659959.git.christophe.leroy@csgroup.eu
Signed-off-by: Sasha Levin <sashal@kernel.org>
