A system crash like this
Failing address: 200000cb7df6f000 TEID: 200000cb7df6f403
Fault in home space mode while using kernel ASCE.
AS:00000002d71bc007 R3:00000003fe5b8007 S:000000011a446000 P:000000015660c13d
Oops: 0038 ilc:3 [#1] PREEMPT SMP
Modules linked in: mlx5_ib ...
CPU: 8 PID: 7556 Comm: bash Not tainted 6.9.0-rc7 #8
Hardware name: IBM 3931 A01 704 (LPAR)
Krnl PSW : 0704e00180000000 0000014b75e7b606 (ap_parse_bitmap_str+0x10e/0x1f8)
R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:2 PM:0 RI:0 EA:3
Krnl GPRS: 0000000000000001 ffffffffffffffc0 0000000000000001 00000048f96b75d3
000000cb00000100 ffffffffffffffff ffffffffffffffff 000000cb7df6fce0
000000cb7df6fce0 00000000ffffffff 000000000000002b 00000048ffffffff
000003ff9b2dbc80 200000cb7df6fcd8 0000014bffffffc0 000000cb7df6fbc8
Krnl Code: 0000014b75e7b5fc: a7840047 brc 8,0000014b75e7b68a
0000014b75e7b600: 18b2 lr %r11,%r2
#0000014b75e7b602: a7f4000a brc 15,0000014b75e7b616
>0000014b75e7b606: eb22d00000e6 laog %r2,%r2,0(%r13)
0000014b75e7b60c: a7680001 lhi %r6,1
0000014b75e7b610: 187b lr %r7,%r11
0000014b75e7b612: 84960021 brxh %r9,%r6,0000014b75e7b654
0000014b75e7b616: 18e9 lr %r14,%r9
Call Trace:
[<0000014b75e7b606>] ap_parse_bitmap_str+0x10e/0x1f8
([<0000014b75e7b5dc>] ap_parse_bitmap_str+0xe4/0x1f8)
[<0000014b75e7b758>] apmask_store+0x68/0x140
[<0000014b75679196>] kernfs_fop_write_iter+0x14e/0x1e8
[<0000014b75598524>] vfs_write+0x1b4/0x448
[<0000014b7559894c>] ksys_write+0x74/0x100
[<0000014b7618a440>] __do_syscall+0x268/0x328
[<0000014b761a3558>] system_call+0x70/0x98
INFO: lockdep is turned off.
Last Breaking-Event-Address:
[<0000014b75e7b636>] ap_parse_bitmap_str+0x13e/0x1f8
Kernel panic - not syncing: Fatal exception: panic_on_oops
occured when /sys/bus/ap/a[pq]mask was updated with a relative mask value
(like +0x10-0x12,+60,-90) with one of the numeric values exceeding INT_MAX.
The fix is simple: use unsigned long values for the internal variables. The
correct checks are already in place in the function but a simple int for
the internal variables was used with the possibility to overflow.
Reported-by: Marc Hartmayer <mhartmay@linux.ibm.com>
Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Tested-by: Marc Hartmayer <mhartmay@linux.ibm.com>
Reviewed-by: Holger Dengler <dengler@linux.ibm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Instead of calling BUG() at runtime introduce and use a prototype for a
non-existing function to produce a link error during compile when a not
supported opcode is used with the __cpacf_query() or __cpacf_check_opcode()
inline functions.
Suggested-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Reviewed-by: Holger Dengler <dengler@linux.ibm.com>
Reviewed-by: Juergen Christ <jchrist@linux.ibm.com>
Cc: stable@vger.kernel.org
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
This is analogous to the reipl's sysfs attribute named equally and enables
tools such as s390-tools' dumpconf to pass additional kernel cmdline
parameters to a stand-alone dumper such as zfcpdump (e.g. to enable
debug output with 'dump_debug' parameter) or ngdump.
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Egorenkov <egorenar@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
This is a refactoring change to reduce code duplication and improve code
reuse.
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Egorenkov <egorenar@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Initialize the correct fields of the nvme dump block.
This bug had not been detected before because first, the fcp and nvme fields
of struct ipl_parameter_block are part of the same union and, therefore,
overlap in memory and second, they are identical in structure and size.
Fixes: d70e38cb1d ("s390: nvme dump support")
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Egorenkov <egorenar@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Use correct symbolic constants IPL_BP_NVME_LEN and IPL_BP0_NVME_LEN
to initialize nvme reipl block when 'scp_data' sysfs attribute is
being updated. This bug had not been detected before because
the corresponding fcp and nvme symbolic constants are equal.
Fixes: 23a457b8d5 ("s390: nvme reipl")
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Egorenkov <egorenar@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
The old implementation of vmcmd sysfs string attributes truncated passed
z/VM CP diagnose X'008' commands which were longer than the max allowed
number of characters but the reported number of written characters was
still equal to the entire length of a given string. This can result in
silent failures of some s390-tools (e.g. dumpconf) which can be very hard
to detect. Therefore, this commit makes a write attempt to a vmcmd sysfs
attribute
* fail with E2BIG error if a given string is longer than the maximum
allowed one
* never destroy the old data in the vmcmd sysfs attribute if the new data
doesn't fit into it entirely
* return the actual number of written characters if it succeeds
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Egorenkov <egorenar@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
z/VM CP diagnose X'008' accepts commands of max 240 characters.
Using a smaller value as a buffer size makes kernel send truncated CP
commands which are longer than the old buffer size. This can result in
invalid CP commands passed to z/VM.
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Egorenkov <egorenar@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
__apply_alternatives() contains a runtime check which verifies that the
size of the to be patched code area is even. Convert this to a compile time
check using a similar ".org" trick, which is already used to verify that
old and new code areas have the same size.
Reviewed-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
There is no user of iucv_root outside of the core IUCV code left.
Therefore remove the EXPORT_SYMBOL.
Acked-by: Alexandra Winter <wintera@linux.ibm.com>
Link: https://lore.kernel.org/r/20240506194454.1160315-7-hca@linux.ibm.com
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Make use of iucv_alloc_device() to get rid of quite some code.
Acked-by: Alexandra Winter <wintera@linux.ibm.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20240506194454.1160315-6-hca@linux.ibm.com
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Make use of iucv_alloc_device() to get rid of quite some code. In addition
this also removes a cast to an incompatible function (clang W=1):
drivers/s390/net/smsgiucv_app.c:176:26: error: cast from 'void (*)(const void *)' to 'void (*)(struct device *)' converts to incompatible function type [-Werror,-Wcast-function-type-strict]
176 | smsg_app_dev->release = (void (*)(struct device *)) kfree;
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Reported-by: Nathan Chancellor <nathan@kernel.org>
Closes: https://lore.kernel.org/r/20240417-s390-drivers-fix-cast-function-type-v1-2-fd048c9903b0@kernel.org
Acked-by: Alexandra Winter <wintera@linux.ibm.com>
Link: https://lore.kernel.org/r/20240506194454.1160315-5-hca@linux.ibm.com
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Make use of iucv_alloc_device() to get rid of quite some code. In addition
this also removes a cast to an incompatible function (clang W=1):
drivers/s390/net/netiucv.c:1716:18: error: cast from 'void (*)(const void *)' to 'void (*)(struct device *)' converts to incompatible function type [-Werror,-Wcast-function-type-strict]
1716 | dev->release = (void (*)(struct device *))kfree;
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Reported-by: Nathan Chancellor <nathan@kernel.org>
Closes: https://lore.kernel.org/r/20240417-s390-drivers-fix-cast-function-type-v1-3-fd048c9903b0@kernel.org
Acked-by: Alexandra Winter <wintera@linux.ibm.com>
Link: https://lore.kernel.org/r/20240506194454.1160315-4-hca@linux.ibm.com
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Make use of iucv_alloc_device() to get rid of quite some code. In addition
this also removes a cast to an incompatible function (clang W=1):
drivers/s390/char/vmlogrdr.c:746:18: error: cast from 'void (*)(const void *)' to 'void (*)(struct device *)' converts to incompatible function type [-Werror,-Wcast-function-type-strict]
746 | dev->release = (void (*)(struct device *))kfree;
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Reported-by: Nathan Chancellor <nathan@kernel.org>
Closes: https://lore.kernel.org/r/20240417-s390-drivers-fix-cast-function-type-v1-1-fd048c9903b0@kernel.org
Acked-by: Alexandra Winter <wintera@linux.ibm.com>
Link: https://lore.kernel.org/r/20240506194454.1160315-3-hca@linux.ibm.com
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Provide iucv_alloc_device() and iucv_release_device() helper functions,
which can be used to deduplicate more or less identical IUCV device
allocation and release code in four different drivers.
Suggested-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Alexandra Winter <wintera@linux.ibm.com>
Link: https://lore.kernel.org/r/20240506194454.1160315-2-hca@linux.ibm.com
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Both do_airq_interrupt() and do_io_interrupt() set
CIF_NOHZ_DELAY. Move it to do_io_irq() to simplify
the code.
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Although the clear-key of neither protected- nor secure-keys is
accessible, this key material should only be visible to the calling
process. So wipe all copies of protected- or secure-keys from stack,
even in case of an error.
Reviewed-by: Harald Freudenberger <freude@linux.ibm.com>
Reviewed-by: Ingo Franzki <ifranzki@linux.ibm.com>
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Holger Dengler <dengler@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Wipe all sensitive data from stack for all IOCTLs, which convert a
clear-key into a protected- or secure-key.
Reviewed-by: Harald Freudenberger <freude@linux.ibm.com>
Reviewed-by: Ingo Franzki <ifranzki@linux.ibm.com>
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Holger Dengler <dengler@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Wipe sensitive data from stack also if the copy_to_user() fails.
Suggested-by: Heiko Carstens <hca@linux.ibm.com>
Reviewed-by: Harald Freudenberger <freude@linux.ibm.com>
Reviewed-by: Ingo Franzki <ifranzki@linux.ibm.com>
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Holger Dengler <dengler@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
It has been removed in commit 2c6b96762f ("s390/fpu: remove TIF_FPU"),
so we should not mention TIF_FPU in the comment here anymore. Since the
remaining parts of the comment just document the obvious fact that
save_user_fpu_regs() saves the FPU state, simply remove the comment now
completely.
Signed-off-by: Thomas Huth <thuth@redhat.com>
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Link: https://lore.kernel.org/r/20240503080648.81461-1-thuth@redhat.com
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Without __unitialized, the following code is generated when
INIT_STACK_ALL_ZERO is enabled:
86: d7 0f f0 a0 f0 a0 xc 160(16,%r15), 160(%r15)
8c: e3 40 f0 a0 00 24 stg %r4, 160(%r15)
92: c0 10 00 00 00 08 larl %r1, 0xa2
98: e3 10 f0 a8 00 24 stg %r1, 168(%r15)
9e: b2 b2 f0 a0 lpswe 160(%r15)
The xc is not adding any security because psw is fully initialized
with the following instructions. Add __unitialized to the psw
definitiation to avoid the superfluous clearing of psw.
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Instead of implementing get_vtimer() use get_cpu_timer()
which does the same.
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
To ease maintenance and further enhancements, convert
the psw_idle() function to C.
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Clear the backchain of the extra stack frame added by the vdso user wrapper
code. This allows the user stack walker to detect and skip the non-standard
stack frame. Without this an incorrect instruction pointer would be added
to stack traces, and stack frame walking would be continued with a more or
less random back chain.
Fixes: aa44433ac4 ("s390: add USER_STACKTRACE support")
Reviewed-by: Jens Remus <jremus@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Introduce and use struct stack_frame_vdso_wrapper within vdso user wrapper
code. With this structure it is possible to automatically generate an
asm-offset define which can be used to save and restore the return address
of the calling function.
Also use STACK_FRAME_USER_OVERHEAD instead of STACK_FRAME_OVERHEAD to
document that the code works with user space stack frames with the standard
stack frame layout.
Fixes: aa44433ac4 ("s390: add USER_STACKTRACE support")
Reviewed-by: Jens Remus <jremus@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Add basic checks to identify invalid instruction pointers when walking
stack frames:
Instruction pointers must
- have even addresses
- be larger than mmap_min_addr
- lower than the asce_limit of the process
Alternatively it would also be possible to walk page tables similar to fast
GUP and verify that the mapping of the corresponding page is executable,
however that seems to be overkill.
Fixes: aa44433ac4 ("s390: add USER_STACKTRACE support")
Reviewed-by: Jens Remus <jremus@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
When walking user stack frames the first stack frame (where the stack
pointer points to) should be skipped: the return address of the current
function is saved in the previous stack frame, not the current stack frame,
which is allocated for to be called functions.
Fixes: aa44433ac4 ("s390: add USER_STACKTRACE support")
Reviewed-by: Jens Remus <jremus@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
The two functions perf_callchain_user() and arch_stack_walk_user() are
nearly identical. Reduce code duplication and add a common helper which can
be called by both functions.
Fixes: aa44433ac4 ("s390: add USER_STACKTRACE support")
Reviewed-by: Jens Remus <jremus@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
By default user space is compiled with standard stack frame layout and not
with the packed stack layout. The vdso code however inherited the
-mpacked-stack compiler option from the kernel. Remove this option to make
sure the vdso is compiled with standard stack frame layout.
This makes sure that the stack frame backchain location for vdso generated
stack frames is the same like for calling code (if compiled with default
options). This allows to manually walk stack frames without DWARF
information, like the kernel is doing it e.g. with arch_stack_walk_user().
Fixes: 4bff8cb545 ("s390: convert to GENERIC_VDSO")
Reviewed-by: Jens Remus <jremus@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Citing Andy Lutomirski from commit dda1e95cee ("x86/vdso: Create
.build-id links for unstripped vdso files"):
"With this change, doing 'make vdso_install' and telling gdb:
set debug-file-directory /lib/modules/KVER/vdso
will enable vdso debugging with symbols. This is useful for
testing, but kernel RPM builds will probably want to manually delete
these symlinks or otherwise do something sensible when they strip
the vdso/*.so files."
Fixes: 4bff8cb545 ("s390: convert to GENERIC_VDSO")
Signed-off-by: Jens Remus <jremus@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
GDB fails to unwind vDSO functions with error message "PC not saved",
for instance when stepping through gettimeofday().
Add -fasynchronous-unwind-tables to CFLAGS to generate .eh_frame
DWARF unwind information for the vDSO C modules.
Fixes: 4bff8cb545 ("s390: convert to GENERIC_VDSO")
Signed-off-by: Jens Remus <jremus@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Add the table type and ACCF validity bits to _SEGMENT_ENTRY_BITS and
_SEGMENT_ENTRY_HARDWARE_BITS{,_LARGE}.
For completeness, introduce _REGION3_ENTRY_HARDWARE_BITS_LARGE and
_REGION3_ENTRY_HARDWARE_BITS, containing the hardware bits used for
large puds and normal puds.
Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Link: https://lore.kernel.org/r/20240429143409.49892-3-imbrenda@linux.ibm.com
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
There is no reason for the read and write softbits to be swapped in the
puds compared to pmds. They are different only because the softbits for
puds were introduced at the same time when the softbits for pmds were
swapped.
The current implementation is not wrong per se, since the macros are
defined correctly; only the documentation does not reflect reality.
With this patch, the read and write softbits for large pmd and large
puds will have the same layout, and will match the existing
documentation.
Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Link: https://lore.kernel.org/r/20240429143409.49892-2-imbrenda@linux.ibm.com
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
- Rework the AP initialization and add missing cleanups to the error path
- Swap IRQ and AP bus/device registration to avoid race conditions
- Export prot_virt_guest symbol
- Introduce AP configuration changes notifier interface to facilitate
modularization of the AP bus
- Add CONFIG_AP kernel configuration option to allow modularization of
the AP bus
- Rework CONFIG_ZCRYPT_DEBUG kernel configuration option description and
dependency and rename it to CONFIG_AP_DEBUG
- Convert sprintf() and snprintf() to sysfs_emit() in CIO code
- Adjust indentation of RELOCS command build step
- Make crypto performance counters upward compatible
- Convert make_page_secure() and gmap_make_secure() to use folio
- Rework channel-utilization-block (CUB) handling in preparation of
introducing additional CUBs
- Use attribute groups to simplify registration, removal and extension
of measurement-related channel-path sysfs attributes
- Add a per-channel-path binary "ext_measurement" sysfs attribute that
provides access to extended channel-path measurement data
- Export measurement data for all channel-measurement-groups (CMG), not
only for a specific ones. This enables support of new CMG data formats
in userspace without the need for kernel changes
- Add a per-channel-path sysfs attribute "speed_bps" that provides the
operating speed in bits per second or 0 if the operating speed is not
available
- The CIO tracepoint subchannel-type field "st" is incorrectly set to
the value of subchannel-enabled SCHIB "ena" field. Fix that
- Do not forcefully limit vmemmap starting address to MAX_PHYSMEM_BITS
- Consider the maximum physical address available to a DCSS segment
(512GB) when memory layout is set up
- Simplify the virtual memory layout setup by reducing the size of
identity mapping vs vmemmap overlap
- Swap vmalloc and Lowcore/Real Memory Copy areas in virtual memory.
This will allow to place the kernel image next to kernel modules
- Move everyting KASLR related from <asm/setup.h> to <asm/page.h>
- Put virtual memory layout information into a structure to improve
code generation
- Currently __kaslr_offset is the kernel offset in both physical and
virtual memory spaces. Uncouple these offsets to allow uncoupling
of the addresses spaces
- Currently the identity mapping base address is implicit and is always
set to zero. Make it explicit by putting into __identity_base persistent
boot variable and use it in proper context
- Introduce .amode31 section start and end macros AMODE31_START and
AMODE31_END
- Introduce OS_INFO entries that do not reference any data in memory,
but rather provide only values
- Store virtual memory layout in OS_INFO. It is read out by makedumpfile,
crash and other tools
- Store virtual memory layout in VMCORE_INFO. It is read out by crash and
other tools when /proc/kcore device is used
- Create additional PT_LOAD ELF program header that covers kernel image
only, so that vmcore tools could locate kernel text and data when virtual
and physical memory spaces are uncoupled
- Uncouple physical and virtual address spaces
- Map kernel at fixed location when KASLR mode is disabled. The location is
defined by CONFIG_KERNEL_IMAGE_BASE kernel configuration value.
- Rework deployment of kernel image for both compressed and uncompressed
variants as defined by CONFIG_KERNEL_UNCOMPRESSED kernel configuration
value
- Move .vmlinux.relocs section in front of the compressed kernel.
The interim section rescue step is avoided as result
- Correct modules thunk offset calculation when branch target is more
than 2GB away
- Kernel modules contain their own set of expoline thunks. Now that the
kernel modules area is less than 4GB away from kernel expoline thunks,
make modules use kernel expolines. Also make EXPOLINE_EXTERN the default
if the compiler supports it
- userfaultfd can insert shared zeropages into processes running VMs,
but that is not allowed for s390. Fallback to allocating a fresh
zeroed anonymous folio and insert that instead
- Re-enable shared zeropages for non-PV and non-skeys KVM guests
- Rename hex2bitmap() to ap_hex2bitmap() and export it for external use
- Add ap_config sysfs attribute to provide the means for setting or
displaying adapters, domains and control domains assigned to a vfio-ap
mediated device in a single operation
- Make vfio_ap_mdev_link_queue() ignore duplicate link requests
- Add write support to ap_config sysfs attribute to allow atomic update
a vfio-ap mediated device state
- Document ap_config sysfs attribute
- Function os_info_old_init() is expected to be called only from a regular
kdump kernel. Enable it to be called from a stand-alone dump kernel
- Address gcc -Warray-bounds warning and fix array size in struct os_info
- s390 does not support SMBIOS, so drop unneeded CONFIG_DMI checks
- Use unwinder instead of __builtin_return_address() with ftrace to
prevent returning of undefined values
- Sections .hash and .gnu.hash are only created when CONFIG_PIE_BUILD
kernel is enabled. Drop these for the case CONFIG_PIE_BUILD is disabled
- Compile kernel with -fPIC and link with -no-pie to allow kpatch feature
always succeed and drop the whole CONFIG_PIE_BUILD option-enabled code
- Add missing virt_to_phys() converter for VSIE facility and crypto
control blocks
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Merge tag 's390-6.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull s390 updates from Alexander Gordeev:
- Store AP Query Configuration Information in a static buffer
- Rework the AP initialization and add missing cleanups to the error
path
- Swap IRQ and AP bus/device registration to avoid race conditions
- Export prot_virt_guest symbol
- Introduce AP configuration changes notifier interface to facilitate
modularization of the AP bus
- Add CONFIG_AP kernel configuration option to allow modularization of
the AP bus
- Rework CONFIG_ZCRYPT_DEBUG kernel configuration option description
and dependency and rename it to CONFIG_AP_DEBUG
- Convert sprintf() and snprintf() to sysfs_emit() in CIO code
- Adjust indentation of RELOCS command build step
- Make crypto performance counters upward compatible
- Convert make_page_secure() and gmap_make_secure() to use folio
- Rework channel-utilization-block (CUB) handling in preparation of
introducing additional CUBs
- Use attribute groups to simplify registration, removal and extension
of measurement-related channel-path sysfs attributes
- Add a per-channel-path binary "ext_measurement" sysfs attribute that
provides access to extended channel-path measurement data
- Export measurement data for all channel-measurement-groups (CMG), not
only for a specific ones. This enables support of new CMG data
formats in userspace without the need for kernel changes
- Add a per-channel-path sysfs attribute "speed_bps" that provides the
operating speed in bits per second or 0 if the operating speed is not
available
- The CIO tracepoint subchannel-type field "st" is incorrectly set to
the value of subchannel-enabled SCHIB "ena" field. Fix that
- Do not forcefully limit vmemmap starting address to MAX_PHYSMEM_BITS
- Consider the maximum physical address available to a DCSS segment
(512GB) when memory layout is set up
- Simplify the virtual memory layout setup by reducing the size of
identity mapping vs vmemmap overlap
- Swap vmalloc and Lowcore/Real Memory Copy areas in virtual memory.
This will allow to place the kernel image next to kernel modules
- Move everyting KASLR related from <asm/setup.h> to <asm/page.h>
- Put virtual memory layout information into a structure to improve
code generation
- Currently __kaslr_offset is the kernel offset in both physical and
virtual memory spaces. Uncouple these offsets to allow uncoupling of
the addresses spaces
- Currently the identity mapping base address is implicit and is always
set to zero. Make it explicit by putting into __identity_base
persistent boot variable and use it in proper context
- Introduce .amode31 section start and end macros AMODE31_START and
AMODE31_END
- Introduce OS_INFO entries that do not reference any data in memory,
but rather provide only values
- Store virtual memory layout in OS_INFO. It is read out by
makedumpfile, crash and other tools
- Store virtual memory layout in VMCORE_INFO. It is read out by crash
and other tools when /proc/kcore device is used
- Create additional PT_LOAD ELF program header that covers kernel image
only, so that vmcore tools could locate kernel text and data when
virtual and physical memory spaces are uncoupled
- Uncouple physical and virtual address spaces
- Map kernel at fixed location when KASLR mode is disabled. The
location is defined by CONFIG_KERNEL_IMAGE_BASE kernel configuration
value.
- Rework deployment of kernel image for both compressed and
uncompressed variants as defined by CONFIG_KERNEL_UNCOMPRESSED kernel
configuration value
- Move .vmlinux.relocs section in front of the compressed kernel. The
interim section rescue step is avoided as result
- Correct modules thunk offset calculation when branch target is more
than 2GB away
- Kernel modules contain their own set of expoline thunks. Now that the
kernel modules area is less than 4GB away from kernel expoline
thunks, make modules use kernel expolines. Also make EXPOLINE_EXTERN
the default if the compiler supports it
- userfaultfd can insert shared zeropages into processes running VMs,
but that is not allowed for s390. Fallback to allocating a fresh
zeroed anonymous folio and insert that instead
- Re-enable shared zeropages for non-PV and non-skeys KVM guests
- Rename hex2bitmap() to ap_hex2bitmap() and export it for external use
- Add ap_config sysfs attribute to provide the means for setting or
displaying adapters, domains and control domains assigned to a
vfio-ap mediated device in a single operation
- Make vfio_ap_mdev_link_queue() ignore duplicate link requests
- Add write support to ap_config sysfs attribute to allow atomic update
a vfio-ap mediated device state
- Document ap_config sysfs attribute
- Function os_info_old_init() is expected to be called only from a
regular kdump kernel. Enable it to be called from a stand-alone dump
kernel
- Address gcc -Warray-bounds warning and fix array size in struct
os_info
- s390 does not support SMBIOS, so drop unneeded CONFIG_DMI checks
- Use unwinder instead of __builtin_return_address() with ftrace to
prevent returning of undefined values
- Sections .hash and .gnu.hash are only created when CONFIG_PIE_BUILD
kernel is enabled. Drop these for the case CONFIG_PIE_BUILD is
disabled
- Compile kernel with -fPIC and link with -no-pie to allow kpatch
feature always succeed and drop the whole CONFIG_PIE_BUILD
option-enabled code
- Add missing virt_to_phys() converter for VSIE facility and crypto
control blocks
* tag 's390-6.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (54 commits)
Revert "s390: Relocate vmlinux ELF data to virtual address space"
KVM: s390: vsie: Use virt_to_phys for crypto control block
s390: Relocate vmlinux ELF data to virtual address space
s390: Compile kernel with -fPIC and link with -no-pie
s390: vmlinux.lds.S: Drop .hash and .gnu.hash for !CONFIG_PIE_BUILD
s390/ftrace: Use unwinder instead of __builtin_return_address()
s390/pci: Drop unneeded reference to CONFIG_DMI
s390/os_info: Fix array size in struct os_info
s390/os_info: Initialize old os_info in standalone dump kernel
docs: Update s390 vfio-ap doc for ap_config sysfs attribute
s390/vfio-ap: Add write support to sysfs attr ap_config
s390/vfio-ap: Ignore duplicate link requests in vfio_ap_mdev_link_queue
s390/vfio-ap: Add sysfs attr, ap_config, to export mdev state
s390/ap: Externalize AP bus specific bitmap reading function
s390/mm: Re-enable the shared zeropage for !PV and !skeys KVM guests
mm/userfaultfd: Do not place zeropages when zeropages are disallowed
s390/expoline: Make modules use kernel expolines
s390/nospec: Correct modules thunk offset calculation
s390/boot: Do not rescue .vmlinux.relocs section
s390/boot: Rework deployment of the kernel image
...
See https://lore.kernel.org/r/20240511171445.904356-1-mic@digikod.net
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Merge tag 'kselftest-fix-vfork-2024-05-12' of git://git.kernel.org/pub/scm/linux/kernel/git/mic/linux
Pull Kselftest fixes from Mickaël Salaün:
"Fix Kselftest's vfork() side effects.
As reported by Kernel Test Robot and Sean Christopherson, some
tests fail since v6.9-rc1 . This is due to the use of vfork() which
introduced some side effects. Similarly, while making it more generic,
a previous commit made some Landlock file system tests flaky, and
subject to the host's file system mount configuration.
This fixes all these side effects by replacing vfork() with clone3()
and CLONE_VFORK, which is cleaner (no arbitrary shared memory) and
makes the Kselftest framework more robust"
Link: https://lore.kernel.org/oe-lkp/202403291015.1fcfa957-oliver.sang@intel.com
Link: https://lore.kernel.org/r/ZjPelW6-AbtYvslu@google.com
Link: https://lore.kernel.org/r/20240511171445.904356-1-mic@digikod.net
* tag 'kselftest-fix-vfork-2024-05-12' of git://git.kernel.org/pub/scm/linux/kernel/git/mic/linux:
selftests/harness: Handle TEST_F()'s explicit exit codes
selftests/harness: Fix vfork() side effects
selftests/harness: Share _metadata between forked processes
selftests/pidfd: Fix wrong expectation
selftests/harness: Constify fixture variants
selftests/landlock: Do not allocate memory in fixture data
selftests/harness: Fix interleaved scheduling leading to race conditions
selftests/harness: Fix fixture teardown
selftests/landlock: Fix FS tests when run on a private mount point
selftests/pidfd: Fix config for pidfd_setns_test
* Fix NULL pointer read on ioctl(KVM_CHECK_EXTENSION) for /dev/kvm.
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Merge tag 'for-linus-6.9' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull kvm fix from Paolo Bonzini:
- Fix NULL pointer read on s390 in ioctl(KVM_CHECK_EXTENSION) for
/dev/kvm
* tag 'for-linus-6.9' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
KVM: s390: Check kvm pointer when testing KVM_CAP_S390_HPAGE_1M
the error interrupt throug the same register, in synopsys_edac
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Merge tag 'edac_urgent_for_v6.9' of git://git.kernel.org/pub/scm/linux/kernel/git/ras/ras
Pull EDAC fix from Borislav Petkov:
- Fix a race condition when clearing error count bits and toggling the
error interrupt throug the same register, in synopsys_edac
* tag 'edac_urgent_for_v6.9' of git://git.kernel.org/pub/scm/linux/kernel/git/ras/ras:
EDAC/synopsys: Fix ECC status and IRQ control race condition
- Ensure that that last level cache ID is set in all cases, in the AMD
CPU topology parsing code, in order to prevent invalid scheduling
domain CPU masks
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Merge tag 'x86_urgent_for_v6.9' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Borislav Petkov:
- Add a new PCI ID which belongs to a new AMD CPU family 0x1a
- Ensure that that last level cache ID is set in all cases, in the AMD
CPU topology parsing code, in order to prevent invalid scheduling
domain CPU masks
* tag 'x86_urgent_for_v6.9' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/topology/amd: Ensure that LLC ID is initialized
x86/amd_nb: Add new PCI IDs for AMD family 0x1a
If TEST_F() explicitly calls exit(code) with code different than 0, then
_metadata->exit_code is set to this code (e.g. KVM_ONE_VCPU_TEST()). We
need to keep in mind that _metadata->exit_code can be KSFT_SKIP while
the process exit code is 0.
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Mark Brown <broonie@kernel.org>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Will Drewry <wad@chromium.org>
Reported-by: Sean Christopherson <seanjc@google.com>
Tested-by: Sean Christopherson <seanjc@google.com>
Closes: https://lore.kernel.org/r/ZjPelW6-AbtYvslu@google.com
Fixes: 0710a1a73f ("selftests/harness: Merge TEST_F_FORK() into TEST_F()")
Link: https://lore.kernel.org/r/20240511171445.904356-11-mic@digikod.net
Signed-off-by: Mickaël Salaün <mic@digikod.net>
Setting the time namespace with CLONE_NEWTIME returns -EUSERS if the
calling thread shares memory with another thread (because of the shared
vDSO), which is the case when it is created with vfork().
Fix pidfd_setns_test by replacing test harness's vfork() call with a
clone3() call with CLONE_VFORK, and an explicit sharing of the
_metadata and self objects.
Replace _metadata->teardown_parent with a new FIXTURE_TEARDOWN_PARENT()
helper that can replace FIXTURE_TEARDOWN(). This is a cleaner approach
and it enables to selectively share the fixture data between the child
process running tests and the parent process running the fixture
teardown. This also avoids updating several tests to not rely on the
self object's copy-on-write property (e.g. storing the returned value of
a fork() call).
Cc: Christian Brauner <brauner@kernel.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: Günther Noack <gnoack@google.com>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Mark Brown <broonie@kernel.org>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Will Drewry <wad@chromium.org>
Reported-by: kernel test robot <oliver.sang@intel.com>
Closes: https://lore.kernel.org/oe-lkp/202403291015.1fcfa957-oliver.sang@intel.com
Fixes: 0710a1a73f ("selftests/harness: Merge TEST_F_FORK() into TEST_F()")
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20240511171445.904356-10-mic@digikod.net
Signed-off-by: Mickaël Salaün <mic@digikod.net>
Unconditionally share _metadata between all forked processes, which
enables to actually catch errors which were previously ignored.
This is required for a following commit replacing vfork() with clone3()
and CLONE_VFORK (i.e. not sharing the full memory) . It should also be
useful to share _metadata to extend expectations to test process's
forks. For instance, this change identified a wrong expectation in
pidfd_setns_test.
Because this _metadata is used by the new XFAIL_ADD(), use a global
pointer initialized in TEST_F(). This is OK because only XFAIL_ADD()
use it, and XFAIL_ADD() already depends on TEST_F().
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Shuah Khan <skhan@linuxfoundation.org>
Cc: Will Drewry <wad@chromium.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20240511171445.904356-9-mic@digikod.net
Signed-off-by: Mickaël Salaün <mic@digikod.net>
Replace a wrong EXPECT_GT(self->child_pid_exited, 0) with EXPECT_GE(),
which will be actually tested on the parent and child sides with a
following commit.
Cc: Shuah Khan <skhan@linuxfoundation.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Christian Brauner <brauner@kernel.org>
Link: https://lore.kernel.org/r/20240511171445.904356-8-mic@digikod.net
Signed-off-by: Mickaël Salaün <mic@digikod.net>
FIXTURE_VARIANT_ADD() types are passed as const pointers to
FIXTURE_TEARDOWN(). Make that explicit by constifying the variants
declarations.
Cc: Shuah Khan <skhan@linuxfoundation.org>
Cc: Will Drewry <wad@chromium.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20240511171445.904356-7-mic@digikod.net
Signed-off-by: Mickaël Salaün <mic@digikod.net>
Do not allocate self->dir_path in the test process because this would
not be visible in the FIXTURE_TEARDOWN() process when relying on
fork()/clone3() instead of vfork().
This change is required for a following commit removing vfork() call to
not break the layout3_fs.* test cases.
Cc: Günther Noack <gnoack@google.com>
Cc: Shuah Khan <skhan@linuxfoundation.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20240511171445.904356-6-mic@digikod.net
Signed-off-by: Mickaël Salaün <mic@digikod.net>
Fix a race condition when running several FIXTURE_TEARDOWN() managing
the same resource. This fixes a race condition in the Landlock file
system tests when creating or unmounting the same directory.
Using clone3() with CLONE_VFORK guarantees that the child and grandchild
test processes are sequentially scheduled. This is implemented with a
new clone3_vfork() helper replacing the fork() call.
This avoids triggering this error in __wait_for_test():
Test ended in some other way [127]
Cc: Christian Brauner <brauner@kernel.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: Günther Noack <gnoack@google.com>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Mark Brown <broonie@kernel.org>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Will Drewry <wad@chromium.org>
Fixes: 41cca0542d ("selftests/harness: Fix TEST_F()'s vfork handling")
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20240511171445.904356-5-mic@digikod.net
Signed-off-by: Mickaël Salaün <mic@digikod.net>
Make sure fixture teardowns are run when test cases failed, including
when _metadata->teardown_parent is set to true.
Make sure only one fixture teardown is run per test case, handling the
case where the test child forks.
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Shengyu Li <shengyu.li.evgeny@gmail.com>
Cc: Shuah Khan <skhan@linuxfoundation.org>
Fixes: 72d7cb5c19 ("selftests/harness: Prevent infinite loop due to Assert in FIXTURE_TEARDOWN")
Fixes: 0710a1a73f ("selftests/harness: Merge TEST_F_FORK() into TEST_F()")
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20240511171445.904356-4-mic@digikod.net
Rule: add
Link: https://lore.kernel.org/stable/20240506165518.474504-4-mic%40digikod.net
Signed-off-by: Mickaël Salaün <mic@digikod.net>
According to the test environment, the mount point of the test's working
directory may be shared or not, which changes the visibility of the
nested "tmp" mount point for the test's parent process calling
umount("tmp").
This was spotted while running tests in containers [1], where mount
points are private.
Cc: Günther Noack <gnoack@google.com>
Cc: Shuah Khan <skhan@linuxfoundation.org>
Link: https://github.com/landlock-lsm/landlock-test-tools/pull/4 [1]
Fixes: 41cca0542d ("selftests/harness: Fix TEST_F()'s vfork handling")
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20240511171445.904356-3-mic@digikod.net
Signed-off-by: Mickaël Salaün <mic@digikod.net>
