- 31 Jan, 2023 1 commit
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Vasily Gorbik authored
Commit bb1520d5 ("s390/mm: start kernel with DAT enabled") doesn't consider online memory holes due to potential memory offlining and erroneously creates pgtables for stand-by memory, which bear RW+X attribute and trigger a warning: RANGE SIZE STATE REMOVABLE BLOCK 0x0000000000000000-0x0000000c3fffffff 49G online yes 0-48 0x0000000c40000000-0x0000000c7fffffff 1G offline 49 0x0000000c80000000-0x0000000fffffffff 14G online yes 50-63 0x0000001000000000-0x00000013ffffffff 16G offline 64-79 s390/mm: Found insecure W+X mapping at address 0xc40000000 WARNING: CPU: 14 PID: 1 at arch/s390/mm/dump_pagetables.c:142 note_page+0x2cc/0x2d8 Map only online memory ranges which fit within identity mapping limit. Fixes: bb1520d5 ("s390/mm: start kernel with DAT enabled") Reviewed-by:
Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by:
Vasily Gorbik <gor@linux.ibm.com> Signed-off-by:
Heiko Carstens <hca@linux.ibm.com>
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- 25 Jan, 2023 13 commits
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Heiko Carstens authored
bpftrace and friends only consider functions present in /sys/kernel/tracing/available_filter_functions. For system calls there is the s390 specific problem that the system call function itself is present via __se_sys##name() while the system call itself is wired up via an __s390x_sys##name() alias. The required DWARF debug information however is only available for the original function, not the alias, but within available_filter_functions only the functions with __s390x_ prefix are available. Which means the required DWARF debug information cannot be found. While this could be solved via tooling, it is easier to change the s390 specific system call wrapper handling. Therefore get rid of this alias handling and implement system call wrappers like most other architectures are doing. In result the implementation generates the following functions: long __s390x_sys##name(struct pt_regs *regs) static inline long __se_sys##name(...) static inline long __do_sys##name(...) __s390x_sys##name() is the visible system call function which is also wired up in the system call table. Its only parameter is a pt_regs variable. This function calls the corresponding __se_sys##name() function, which has as many parameters like the system call definition. This function in turn performs all zero and sign extensions of all system call parameters, taken from the pt_regs structure, and finally calls __do_sys##name(). __do_sys##name() is the actual inlined system call function implementation. For all 64 bit system calls there is a 31/32 bit system call function __s390_sys##name() generated, which handles all system call parameters correctly as required by compat handling. This function may be wired up within the compat system call table, unless there exists an explicit compat system call function, which is then used instead. Reported-by:
Ilya Leoshkevich <iii@linux.ibm.com> Tested-by:
Sven Schnelle <svens@linux.ibm.com> Signed-off-by:
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Heiko Carstens authored
Reviewed-by:
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Heiko Carstens authored
Move __S390_SYS_STUBx() the end of the CONFIG_COMPAT section, so both variants (compat and non-compat) are close together and can be easily compared. Reviewed-by:
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Heiko Carstens authored
Remove __SC_COMPAT_TYPE define which is an unused leftover. Reviewed-by:
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Heiko Carstens authored
SYSCALL_METADATA() is only supposed to be used for non-compat system calls. Otherwise there would be a name clash. This also removes the inconsistency that s390 is the only architecture which uses SYSCALL_METADATA() for compat system calls, and even that only for compat system calls without parameters. Only two such compat system calls exist. Reviewed-by:
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Ilya Leoshkevich authored
When debugging vmlinux with QEMU + GDB, the following GDB error may occur: (gdb) c Continuing. Warning: Cannot insert breakpoint -1. Cannot access memory at address 0xffffffffffff95c0 Command aborted. (gdb) The reason is that, when .interp section is present, GDB tries to locate the file specified in it in memory and put a number of breakpoints there (see enable_break() function in gdb/solib-svr4.c). Sometimes GDB finds a bogus location that matches its heuristics, fails to set a breakpoint and stops. This makes further debugging impossible. The .interp section contains misleading information anyway (vmlinux does not need ld.so), so fix by discarding it. Signed-off-by: -
Thomas Richter authored
Simplify the use of constants PMC_INIT and PMC_RELEASE. Suggested-by:
Thomas Richter <tmricht@linux.ibm.com> Signed-off-by:
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Thomas Richter authored
With no in-kernel user, the source files can be merged. Move all functions and the variable definitions to file perf_cpum_cf.c This file now contains all the necessary functions and definitions for the CPU Measurement counter facility device driver. The files cpu_mcf.h and perf_cpum_cf_common.c are deleted. Signed-off-by:
Hendrik Brueckner <brueckner@linux.ibm.com> Signed-off-by:
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Thomas Richter authored
Commit 17bebcc6 ("s390/cpum_cf: Add minimal in-kernel interface for counter measurements") introduced a small in-kernel interface for CPU Measurement counter facility. There are no users of this interface, therefore remove it. The following functions are removed: kernel_cpumcf_alert(), kernel_cpumcf_begin(), kernel_cpumcf_end(), kernel_cpumcf_avail() there is no need for them anymore. With the removal of function kernel_cpumcf_alert(), also remove member alert in struct cpu_cf_events. Its purpose was to counter measurement alert interrupts for the in-kernel interface. Signed-off-by:
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Thomas Richter authored
Function stccm_avail() is defined in a header file and the only user is one single source file. Move this function to the source file where it is also used and remove it from the header file. No functional change. Signed-off-by:
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Thomas Richter authored
Function cpum_cf_ctrset_size() is defined in one source file and the only user is in another source file. Move this function to the source file where it is used and remove its prototype from the header file. No functional change. Signed-off-by:
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Thomas Richter authored
To remove an event from the CPU Measurement counter facility use the lock/unlock scheme as done in event creation. Remove the atomic_add_unless function to make the code easier. Signed-off-by:
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Heiko Carstens authored
The unsigned long long type is a leftover of the 31 bit area. Get rid of it. Signed-off-by:
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- 22 Jan, 2023 15 commits
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Tony Krowiak authored
Increase the maximum time to wait for verification of a queue reset operation to 200ms. Signed-off-by:
Tony Krowiak <akrowiak@linux.ibm.com> Reviewed-by:
Jason J. Herne <jjherne@linux.ibm.com> Reviewed-by:
Harald Freudenberger <freude@linux.ibm.com> Link: https://lore.kernel.org/r/20230118203111.529766-7-akrowiak@linux.ibm.comSigned-off-by:
Christian Borntraeger <borntraeger@linux.ibm.com> Signed-off-by:
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Tony Krowiak authored
Some response codes returned from the queue reset function are not being handled correctly; this patch fixes them: 1. Response code 3, AP queue deconfigured: Deconfiguring an AP adapter resets all of its queues, so this is handled by indicating the reset verification completed successfully. 2. For all response codes other than 0 (normal reset completion), 2 (queue reset in progress) and 3 (AP deconfigured), the -EIO error will be returned from the vfio_ap_mdev_reset_queue() function. In all cases, all fields of the status word other than the response code will be set to zero, so it makes no sense to check status bits. Signed-off-by:
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Tony Krowiak authored
Verification that the asynchronous ZAPQ function has completed only needs to be done when the response code indicates the function was successfully initiated; so, let's call the apq_reset_check function immediately after the response code zero is returned from the ZAPQ. Signed-off-by:
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Tony Krowiak authored
To eliminate the repeated calls to the PQAP(ZAPQ) function to verify that a reset in progress completed successfully and ensure that error response codes get appropriately logged, let's call the apq_reset_check() function when the ZAPQ response code indicates that a reset that is already in progress. Signed-off-by:
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Tony Krowiak authored
The vfio_ap_mdev_reset_queue() function does not check the status response code returned form the PQAP(TAPQ) function when verifying the queue's status; consequently, there is no way of knowing whether verification failed because the wait time was exceeded, or because the PQAP(TAPQ) failed. This patch adds a function to check the status response code from the PQAP(TAPQ) instruction and logs an appropriate message if it fails. Signed-off-by:
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Tony Krowiak authored
The vfio_ap_mdev_reset_queue() function contains a loop to verify that the reset successfully completes within 40ms. This patch moves that loop into a separate function. Signed-off-by:
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Vasily Gorbik authored
That's an adaptation of commit f3a112c0 ("x86,rethook,kprobes: Replace kretprobe with rethook on x86") to s390. Replaces the kretprobe code with rethook on s390. With this patch, kretprobe on s390 uses the rethook instead of kretprobe specific trampoline code. Tested-by:
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Thomas Richter authored
The CPU Measurement Sampling Facility (CPUM_SF) installs large buffers to save samples collected by hardware. These buffers are organized as Sample Data Buffer Tables (SDBT) and Sample Data Buffers (SDB). SDBs contain the samples which are extracted and saved in the perf ring buffer. The SDBTs are chained using real addresses and refer to SDBs using real addresses. The diagnostic sampling setup uses buffers provided by the process which invokes perf_event_open system call. The buffers are memory mapped. The buffers have been allocated by the kernel event subsystem. Add proper virtual to phyiscal address translation to the buffer chaining. The current constraint which requires virtual equals real address layout is removed. Signed-off-by:
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Thomas Richter authored
Macro AUX_SDB_NUM() has three parameters. The first one is not used. Remove the first parameter. Also convert the macros to inline functions. No functional change. Signed-off-by:
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Thomas Richter authored
The CPU Measurement Sampling Facility (CPUM_SF) installs large buffers to save samples collected by hardware. These buffers are organized as Sample Data Buffer Tables (SDBT) and Sample Data Buffers (SDB). SDBs contain the samples which are extracted and saved in the perf ring buffer. The SDBTs are chained using real addresses and refer to SDBs using real addresses. Adds proper virtual to phyiscal address translation to the buffer chaining. The current constraint which requires virtual equals real address layout is removed. Signed-off-by:
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Thomas Richter authored
Remove debug statements from function setup_pmc_cpu(). The debug statement displays a pointer value to a per cpu variable. This pointer value is printed nowhere else, so it has no use for cross reference. No functional change. Signed-off-by:
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Thomas Richter authored
Some inline helper functions are defined in a header file but used in only one source file. Move these functions to the source file. No functional change. Signed-off-by:
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Jiapeng Chong authored
Swap is a function interface that provides exchange function. To avoid code duplication, we can use swap function. ./arch/s390/mm/vmem.c:680:10-11: WARNING opportunity for swap(). [hca@linux.ibm.com: get rid of all temp variables] Link: https://bugzilla.openanolis.cn/show_bug.cgi?id=3786Reported-by:
Abaci Robot <abaci@linux.alibaba.com> Signed-off-by:
Jiapeng Chong <jiapeng.chong@linux.alibaba.com> Link: https://lore.kernel.org/r/20230117060223.58583-1-jiapeng.chong@linux.alibaba.comSigned-off-by:
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Vineeth Vijayan authored
css_schedule_reprobe() function calls the evaluation for CSS_EVAL_UNREG which is specific to the idset of unregistered subchannels. This evaluation was introduced because, previously, if the underlying device become not-accessible, the subchannel was unregistered. But, in the recent changes in cio,with the commit '2297791c s390/cio: dont unregister subchannel from child-drivers', we no longer unregister the subchannels just because of a non-operational device. This allows to have subchannels without any operational device connected on it. So, a css_schedule_reprobe function on unregistered subchannel does not have any effect. Change this functionality to evaluate the subchannels which does not have a working path to the device. This could be due the erroneous device or due to the erraneous path. Evaluate based on the values of OPM and PAM&POM. Here we introduced a new idset function,to keep I/O subchannels in the idset when the last seen status indicates that the device has no working path. A device has no working path if all available paths have been tried without success.A failed I/O attempt on a path is indicated as a 0 bit value in the POM mask. By looking at the POM mask bit values of available paths (1 in PAM) that Linux is supposed to use (1 in vary mask OPM), we can identify a non-working device as a device where the bit-wise and of the PAM, POM and OPM mask return 0. css_schedule_reprobe() is being used by dasd-driver and chsc-cio component. dasd driver, when it detects a change in the pathgroup, invokes the re-evaluation of the subchannel. And chsc-cio component upon a CRW event, (resource accessibility event). In both the cases, it makes much better sense to re-evalute the subchannel with no-valid path. Signed-off-by:
Vineeth Vijayan <vneethv@linux.ibm.com> Reported-by:
Eric Farman <farman@linux.ibm.com> Reviewed-by:
Peter Oberparleiter <oberpar@linux.ibm.com> Tested-by:
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Christophe JAILLET authored
strtobool() is the same as kstrtobool(). However, the latter is more used within the kernel. In order to remove strtobool() and slightly simplify kstrtox.h, switch to the other function name. Signed-off-by:
Christophe JAILLET <christophe.jaillet@wanadoo.fr> Link: https://lore.kernel.org/r/58a3ed2e21903a93dfd742943b1e6936863ca037.1673708887.git.christophe.jaillet@wanadoo.frSigned-off-by:
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- 17 Jan, 2023 2 commits
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Heiko Carstens authored
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Heiko Carstens authored
GCC 11.1.0 and 11.2.0 generate a wrong warning when compiling the kernel e.g. with allmodconfig: arch/s390/kernel/setup.c: In function ‘setup_lowcore_dat_on’: ./include/linux/fortify-string.h:57:33: error: ‘__builtin_memcpy’ reading 128 bytes from a region of size 0 [-Werror=stringop-overread] ... arch/s390/kernel/setup.c:526:9: note: in expansion of macro ‘memcpy’ 526 | memcpy(abs_lc->cregs_save_area, S390_lowcore.cregs_save_area, | ^~~~~~ This could be addressed by using absolute_pointer() with the S390_lowcore macro, but this is not a good idea since this generates worse code for performance critical paths. Therefore simply use a for loop to copy the array in question and get rid of the warning. Reported-by:Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by:
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- 13 Jan, 2023 9 commits
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Vineeth Vijayan authored
Remove Cornelia's email address from the file as suggested by her. List linux-s390 mailing-list address as the primary contact instead. Link: https://lore.kernel.org/linux-s390/8735d0oiq6.fsf@redhat.com/Signed-off-by:
Cornelia Huck <cohuck@redhat.com> Signed-off-by:
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Christophe JAILLET authored
The commit in Fixes: has switch the order of a sysfs_create_group() and a kzalloc(). It correctly removed the now useless kfree() but forgot to add a sysfs_remove_group() in case of (unlikely) memory allocation failure. Add it now. Fixes: 260f3ea1 ("s390/vfio-ap: move probe and remove callbacks to vfio_ap_ops.c") Signed-off-by:
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Heiko Carstens authored
Move __amode31_base declaration to proper header file to get rid of arch/s390/boot/startup.c:24:15: warning: symbol '__amode31_base' was not declared. Should it be static? Signed-off-by: -
Alexander Gordeev authored
Move Absolute Lowcore Area allocation to the decompressor. As result, get_abs_lowcore() and put_abs_lowcore() access brackets become really straight and do not require complex execution context analysis and LAP and interrupts tackling. Reviewed-by:
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Alexander Gordeev authored
Move Real Memory Copy Area allocation to the decompressor. As result, memcpy_real() and memcpy_real_iter() movers become usable since the very moment the kernel starts. Reviewed-by:
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Alexander Gordeev authored
Currently the decompressor sets up only identity mapping. Allow adding more address range types as a prerequisite for allocation of kernel fixed mappings. Signed-off-by:
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Alexander Gordeev authored
The identity mapping is created in the decompressor, there is no need to have the same functionality in the kasan setup code. Thus, remove it. Remove the 4KB pages check for first 1MB since there is no need to take care of the lowcore pages. Acked-by:
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Alexander Gordeev authored
As the kernel is executed in DAT-on mode only, remove unnecessary DAT bit check together with the dead code. Reviewed-by:
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Alexander Gordeev authored
The setup of the kernel virtual address space is spread throughout the sources, boot stages and config options like this: 1. The available physical memory regions are queried and stored as mem_detect information for later use in the decompressor. 2. Based on the physical memory availability the virtual memory layout is established in the decompressor; 3. If CONFIG_KASAN is disabled the kernel paging setup code populates kernel pgtables and turns DAT mode on. It uses the information stored at step [1]. 4. If CONFIG_KASAN is enabled the kernel early boot kasan setup populates kernel pgtables and turns DAT mode on. It uses the information stored at step [1]. The kasan setup creates early_pg_dir directory and directly overwrites swapper_pg_dir entries to make shadow memory pages available. Move the kernel virtual memory setup to the decompressor and start the kernel with DAT turned on right from the very first istruction. That completely eliminates the boot phase when the kernel runs in DAT-off mode, simplies the overall design and consolidates pgtables setup. The identity mapping is created in the decompressor, while kasan shadow mappings are still created by the early boot kernel code. Share with decompressor the existing kasan memory allocator. It decreases the size of a newly requested memory block from pgalloc_pos and ensures that kernel image is not overwritten. pgalloc_low and pgalloc_pos pointers are made preserved boot variables for that. Use the bootdata infrastructure to setup swapper_pg_dir and invalid_pg_dir directories used by the kernel later. The interim early_pg_dir directory established by the kasan initialization code gets eliminated as result. As the kernel runs in DAT-on mode only the PSW_KERNEL_BITS define gets PSW_MASK_DAT bit by default. Additionally, the setup_lowcore_dat_off() and setup_lowcore_dat_on() routines get merged, since there is no DAT-off mode stage anymore. The memory mappings are created with RW+X protection that allows the early boot code setting up all necessary data and services for the kernel being booted. Just before the paging is enabled the memory protection is changed to RO+X for text, RO+NX for read-only data and RW+NX for kernel data and the identity mapping. Reviewed-by:
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