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2023-02-10powerpc/bpf/32: Only set a stack frame when necessaryChristophe Leroy
Until now a stack frame was set at all time due to the need to keep tail call counter in the stack. But since commit 89d21e259a94 ("powerpc/bpf/32: Fix Oops on tail call tests") the tail call counter is passed via register r4. It is therefore not necessary anymore to have a stack frame for that. Just like PPC64, implement bpf_has_stack_frame() and only sets the frame when needed. The difference with PPC64 is that PPC32 doesn't have a redzone, so the stack is required as soon as non volatile registers are used or when tail call count is set up. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> [mpe: Fix commit reference in change log] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/62d7b654a3cfe73d998697cb29bbc5ffd89bfdb1.1675245773.git.christophe.leroy@csgroup.eu
2023-02-10powerpc/bpf/32: No need to zeroise r4 when not doing tail callChristophe Leroy
r4 is cleared at function entry and used as tail call count. But when the function does not perform tail call, r4 is ignored, so no need to clear it. Replace it by a NOP in that case. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/9c5440b2b6d90a78600257433ac499b5c5101fbb.1675245773.git.christophe.leroy@csgroup.eu
2023-02-10powerpc: Remove __kernel_text_address() in show_instructions()Christophe Leroy
That test was introducted in 2006 by commit 00ae36de49cc ("[POWERPC] Better check in show_instructions"). At that time, there was no BPF progs. As seen in message of commit 89d21e259a94 ("powerpc/bpf/32: Fix Oops on tail call tests"), when a page fault occurs in test_bpf.ko for instance, the code is dumped as XXXXXXXXs. Allthough __kernel_text_address() checks is_bpf_text_address(), it seems it is not enough. Today, show_instructions() uses get_kernel_nofault() to read the code, so there is no real need for additional verifications. ARM64 and x86 don't do any additional check before dumping instructions. Do the same and remove __kernel_text_address() in show_instructions(). Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/4fd69ef7945518c3e27f96b95046a5c1468d35bf.1675245773.git.christophe.leroy@csgroup.eu
2023-02-10powerpc/mce: log the error for all unrecoverable errorsGanesh Goudar
For all unrecoverable errors we are missing to log the error, Since machine_check_log_err() is not getting called for unrecoverable errors. machine_check_log_err() is called from deferred handler, To run deferred handlers we have to do irq work raise from the exception handler. For recoverable errors exception vector code takes care of running deferred handlers. For unrecoverable errors raise irq work in save_mce_event(), So that we log the error from MCE deferred handler. Log without this change MCE: CPU27: machine check (Severe) Real address Load/Store (foreign/control memory) [Not recovered] MCE: CPU27: PID: 10580 Comm: inject-ra-err NIP: [0000000010000df4] MCE: CPU27: Initiator CPU MCE: CPU27: Unknown Log with this change MCE: CPU24: machine check (Severe) Real address Load/Store (foreign/control memory) [Not recovered] MCE: CPU24: PID: 1589811 Comm: inject-ra-err NIP: [0000000010000e48] MCE: CPU24: Initiator CPU MCE: CPU24: Unknown RTAS: event: 5, Type: Platform Error (224), Severity: 3 Signed-off-by: Ganesh Goudar <ganeshgr@linux.ibm.com> Reviewed-by: Mahesh Salgaonkar <mahesh@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20230201095933.129482-1-ganeshgr@linux.ibm.com
2023-02-09selftests/powerpc: Add automatically allocating read_fileBenjamin Gray
A couple of tests roll their own auto-allocating file read logic. Add a generic implementation and convert them to use it. Signed-off-by: Benjamin Gray <bgray@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20230203003947.38033-6-bgray@linux.ibm.com
2023-02-09selftests/powerpc: Add {read,write}_{long,ulong}Benjamin Gray
Add helper functions to read and write (unsigned) long values directly from/to files. One of the kernel interfaces uses hex strings, so we need to allow passing a base too. Signed-off-by: Benjamin Gray <bgray@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20230203003947.38033-5-bgray@linux.ibm.com
2023-02-09selftests/powerpc: Parse long/unsigned long value safelyBenjamin Gray
Often a file is expected to hold an integral value. Existing functions will use a C stdlib function like atoi or strtol to parse the file. These operations are error prone, with complicated error conditions (atoi returns 0 if not a number, and is undefined behaviour if not in range. strtol returns 0 if not a number, and LONG_MIN/MAX if not in range + sets errno to ERANGE). Signed-off-by: Benjamin Gray <bgray@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20230203003947.38033-4-bgray@linux.ibm.com
2023-02-09selftests/powerpc: Add read/write debugfs file, intBenjamin Gray
Debugfs files are not always integers, so make *_file return/write a byte buffer, and *_int deal with int values specifically. This increases consistency with the other file read/write helpers. Signed-off-by: Benjamin Gray <bgray@linux.ibm.com> Reviewed-by: Andrew Donnellan <ajd@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20230203003947.38033-3-bgray@linux.ibm.com
2023-02-09selftests/powerpc: Add generic read/write file utilBenjamin Gray
File read/write is reimplemented in about 5 different ways in the various PowerPC selftests. This indicates it should be a common util. Add a common read_file / write_file implementation and convert users to it where (easily) possible. Signed-off-by: Benjamin Gray <bgray@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20230203003947.38033-2-bgray@linux.ibm.com
2023-02-08powerpc/iommu: fix memory leak with using debugfs_lookup()Greg Kroah-Hartman
When calling debugfs_lookup() the result must have dput() called on it, otherwise the memory will leak over time. To make things simpler, just call debugfs_lookup_and_remove() instead which handles all of the logic at once. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20230202141919.2298821-1-gregkh@linuxfoundation.org
2023-02-08powerpc/64s/radix: Remove TLB_FLUSH_ALL test from range flushesNicholas Piggin
This looks like it came across from x86, but x86 uses TLB_FLUSH_ALL as a parameter to internal functions. Powerpc never sets it anywhere. Remove the associated logic and leave a warning for now. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20230203111718.1149852-4-npiggin@gmail.com
2023-02-08powerpc/64s/radix: mm->context.id should always be validNicholas Piggin
The MMU_NO_CONTEXT checks are an unnecessary complication. Make these warn to prepare to remove them in future. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20230203111718.1149852-3-npiggin@gmail.com
2023-02-08powerpc/64s/radix: Remove need_flush_all test from radix__tlb_flushNicholas Piggin
need_flush_all is only set by arch code to instruct generic tlb_flush to flush all. It is never set by powerpc, so it can be removed. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20230203111718.1149852-2-npiggin@gmail.com
2023-02-08powerpc: Disable CPU unknown by CLANG when CC_IS_CLANGChristophe Leroy
CLANG only knows the following CPUs: generic, 440, 450, 601, 602, 603, 603e, 603ev, 604, 604e, 620, 630, g3, 7400, g4, 7450, g4+, 750, 8548, 970, g5, a2, e500, e500mc, e5500, power3, pwr3, power4, pwr4, power5, pwr5, power5x, pwr5x, power6, pwr6, power6x, pwr6x, power7, pwr7, power8, pwr8, power9, pwr9, power10, pwr10, powerpc, ppc, ppc32, powerpc64, ppc64, powerpc64le, ppc64le, futur Disable other ones when CC_IS_CLANG. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/e62892e32c14a7a5738c597e39e0082cb0abf21c.1675335659.git.christophe.leroy@csgroup.eu
2023-02-07powerpc/pci: Add option for using pci_to_OF_bus_mapPali Rohár
The "pci-OF-bus-map" property was declared deprecated in 2006 [1] and to the best of everyone's knowledge is not used by anything anymore [2]. The creation of the property was disabled on powermac (arch/powerpc) in 2005 by commit 35499c0195e4 ("powerpc: Merge in 64-bit powermac support."). But it is still created by default on CHRP. On powermac the actual map (pci_to_OF_bus_map) is still used by default, even though the device tree property is not created. Add an option to enable/disable use of the pci_to_OF_bus_map, and creation of the property (on CHRP). Disabling the option allows enabling CONFIG_PPC_PCI_BUS_NUM_DOMAIN_DEPENDENT which allows "normal" bus numbering and more than 256 buses, like 64-bit and other architectures. Mark the new option as default n, the intention is that the option and the code will be removed in a future release. [1]: https://lore.kernel.org/linuxppc-dev/1148016268.13249.14.camel@localhost.localdomain/ [2]: https://lore.kernel.org/all/575f239205e8635add81c9f902b7d9db7beb83ea.camel@kernel.crashing.org/ Signed-off-by: Pali Rohár <pali@kernel.org> [mpe: Reword commit & help text, shrink option name, rework to fix build errors] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20230206113902.1857123-1-mpe@ellerman.id.au
2023-02-07powerpc/64s/interrupt: Fix interrupt exit race with security mitigation switchNicholas Piggin
The RFI and STF security mitigation options can flip the interrupt_exit_not_reentrant static branch condition concurrently with the interrupt exit code which tests that branch. Interrupt exit tests this condition to set MSR[EE|RI] for exit, then again in the case a soft-masked interrupt is found pending, to recover the MSR so the interrupt can be replayed before attempting to exit again. If the condition changes between these two tests, the MSR and irq soft-mask state will become corrupted, leading to warnings and possible crashes. For example, if the branch is initially true then false, MSR[EE] will be 0 but PACA_IRQ_HARD_DIS clear and EE may not get enabled, leading to warnings in irq_64.c. Fixes: 13799748b957 ("powerpc/64: use interrupt restart table to speed up return from interrupt") Cc: stable@vger.kernel.org # v5.14+ Reported-by: Sachin Sant <sachinp@linux.ibm.com> Tested-by: Sachin Sant <sachinp@linux.ibm.com> Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20230206042240.92103-1-npiggin@gmail.com
2023-02-06powerpc/kexec_file: fix implicit decl errorRandy Dunlap
kexec (PPC64) code calls memory_hotplug_max(). Add the header declaration for it from <asm/mmzone.h>. Using <linux/mmzone.h> does not work since the #include for <asm/mmzone.h> depends on CONFIG_NUMA=y, which is not always set. Fixes this build error/warning: arch/powerpc/kexec/file_load_64.c: In function 'kexec_extra_fdt_size_ppc64': arch/powerpc/kexec/file_load_64.c:993:33: error: implicit declaration of function 'memory_hotplug_max' 993 | usm_entries = ((memory_hotplug_max() / drmem_lmb_size()) + | ^~~~~~~~~~~~~~~~~~ Fixes: fc546faa5595 ("powerpc/kexec_file: Count hot-pluggable memory in FDT estimate") Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20230204172206.7662-1-rdunlap@infradead.org
2023-02-02powerpc: Don't select ARCH_WANTS_NO_INSTRMichael Ellerman
Commit 41b7a347bf14 ("powerpc: Book3S 64-bit outline-only KASAN support") added a select of ARCH_WANTS_NO_INSTR, because it also added some uses of noinstr. However noinstr is always defined, regardless of ARCH_WANTS_NO_INSTR, so there's no need to select it just for that. As PeterZ says [1]: Note that by selecting ARCH_WANTS_NO_INSTR you effectively state to abide by its rules. As of now the powerpc code does not abide by those rules, and trips some new warnings added by Peter in linux-next. So until the code can be fixed to avoid those warnings, disable ARCH_WANTS_NO_INSTR. Note that ARCH_WANTS_NO_INSTR is also used to gate building KCOV and parts of KCSAN. However none of the noinstr annotations in powerpc were added for KCOV or KCSAN, instead instrumentation is blocked at the file level using KCOV_INSTRUMENT_foo.o := n. [1]: https://lore.kernel.org/linuxppc-dev/Y9t6yoafrO5YqVgM@hirez.programming.kicks-ass.net Reported-by: Sachin Sant <sachinp@linux.ibm.com> Suggested-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2023-02-02powerpc/64s: Reconnect tlb_flush() to hash__tlb_flush()Michael Ellerman
Commit baf1ed24b27d ("powerpc/mm: Remove empty hash__ functions") removed some empty hash MMU flushing routines, but got a bit overeager and also removed the call to hash__tlb_flush() from tlb_flush(). In regular use this doesn't lead to any noticable breakage, which is a little concerning. Presumably there are flushes happening via other paths such as arch_leave_lazy_mmu_mode(), and/or a bit of luck. Fix it by reinstating the call to hash__tlb_flush(). Fixes: baf1ed24b27d ("powerpc/mm: Remove empty hash__ functions") Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20230131111407.806770-1-mpe@ellerman.id.au
2023-02-01powerpc/kexec_file: Count hot-pluggable memory in FDT estimateSourabh Jain
On Systems where online memory is lesser compared to max memory, the kexec_file_load system call may fail to load the kdump kernel with the below errors: "Failed to update fdt with linux,drconf-usable-memory property" "Error setting up usable-memory property for kdump kernel" This happens because the size estimation for usable memory properties for the kdump kernel's FDT is based on the online memory whereas the usable memory properties include max memory. In short, the hot-pluggable memory is not accounted for while estimating the size of the usable memory properties. The issue is addressed by calculating usable memory property size using max hotplug address instead of the last online memory address. Fixes: 2377c92e37fe ("powerpc/kexec_file: fix FDT size estimation for kdump kernel") Signed-off-by: Sourabh Jain <sourabhjain@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20230131030615.729894-1-sourabhjain@linux.ibm.com
2023-01-31powerpc/64s/radix: Fix RWX mapping with relocated kernelMichael Ellerman
If a relocatable kernel is loaded at a non-zero address and told not to relocate to zero (kdump or RELOCATABLE_TEST), the mapping of the interrupt code at zero is left with RWX permissions. That is a security weakness, and leads to a warning at boot if CONFIG_DEBUG_WX is enabled: powerpc/mm: Found insecure W+X mapping at address 00000000056435bc/0xc000000000000000 WARNING: CPU: 1 PID: 1 at arch/powerpc/mm/ptdump/ptdump.c:193 note_page+0x484/0x4c0 CPU: 1 PID: 1 Comm: swapper/0 Not tainted 6.2.0-rc1-00001-g8ae8e98aea82-dirty #175 Hardware name: IBM pSeries (emulated by qemu) POWER9 (raw) 0x4e1202 0xf000005 of:SLOF,git-dd0dca hv:linux,kvm pSeries NIP: c0000000004a1c34 LR: c0000000004a1c30 CTR: 0000000000000000 REGS: c000000003503770 TRAP: 0700 Not tainted (6.2.0-rc1-00001-g8ae8e98aea82-dirty) MSR: 8000000002029033 <SF,VEC,EE,ME,IR,DR,RI,LE> CR: 24000220 XER: 00000000 CFAR: c000000000545a58 IRQMASK: 0 ... NIP note_page+0x484/0x4c0 LR note_page+0x480/0x4c0 Call Trace: note_page+0x480/0x4c0 (unreliable) ptdump_pmd_entry+0xc8/0x100 walk_pgd_range+0x618/0xab0 walk_page_range_novma+0x74/0xc0 ptdump_walk_pgd+0x98/0x170 ptdump_check_wx+0x94/0x100 mark_rodata_ro+0x30/0x70 kernel_init+0x78/0x1a0 ret_from_kernel_thread+0x5c/0x64 The fix has two parts. Firstly the pages from zero up to the end of interrupts need to be marked read-only, so that they are left with R-X permissions. Secondly the mapping logic needs to be taught to ensure there is a page boundary at the end of the interrupt region, so that the permission change only applies to the interrupt text, and not the region following it. Fixes: c55d7b5e6426 ("powerpc: Remove STRICT_KERNEL_RWX incompatibility with RELOCATABLE") Reported-by: Sachin Sant <sachinp@linux.ibm.com> Tested-by: Sachin Sant <sachinp@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20230110124753.1325426-2-mpe@ellerman.id.au
2023-01-31powerpc/64s/radix: Fix crash with unaligned relocated kernelMichael Ellerman
If a relocatable kernel is loaded at an address that is not 2MB aligned and told not to relocate to zero, the kernel can crash due to mark_rodata_ro() incorrectly changing some read-write data to read-only. Scenarios where the misalignment can occur are when the kernel is loaded by kdump or using the RELOCATABLE_TEST config option. Example crash with the kernel loaded at 5MB: Run /sbin/init as init process BUG: Unable to handle kernel data access on write at 0xc000000000452000 Faulting instruction address: 0xc0000000005b6730 Oops: Kernel access of bad area, sig: 11 [#1] LE PAGE_SIZE=64K MMU=Radix SMP NR_CPUS=2048 NUMA pSeries CPU: 1 PID: 1 Comm: init Not tainted 6.2.0-rc1-00011-g349188be4841 #166 Hardware name: IBM pSeries (emulated by qemu) POWER9 (raw) 0x4e1202 0xf000005 of:SLOF,git-5b4c5a hv:linux,kvm pSeries NIP: c0000000005b6730 LR: c000000000ae9ab8 CTR: 0000000000000380 REGS: c000000004503250 TRAP: 0300 Not tainted (6.2.0-rc1-00011-g349188be4841) MSR: 8000000000009033 <SF,EE,ME,IR,DR,RI,LE> CR: 44288480 XER: 00000000 CFAR: c0000000005b66ec DAR: c000000000452000 DSISR: 0a000000 IRQMASK: 0 ... NIP memset+0x68/0x104 LR zero_user_segments.constprop.0+0xa8/0xf0 Call Trace: ext4_mpage_readpages+0x7f8/0x830 ext4_readahead+0x48/0x60 read_pages+0xb8/0x380 page_cache_ra_unbounded+0x19c/0x250 filemap_fault+0x58c/0xae0 __do_fault+0x60/0x100 __handle_mm_fault+0x1230/0x1a40 handle_mm_fault+0x120/0x300 ___do_page_fault+0x20c/0xa80 do_page_fault+0x30/0xc0 data_access_common_virt+0x210/0x220 This happens because mark_rodata_ro() tries to change permissions on the range _stext..__end_rodata, but _stext sits in the middle of the 2MB page from 4MB to 6MB: radix-mmu: Mapped 0x0000000000000000-0x0000000000200000 with 2.00 MiB pages (exec) radix-mmu: Mapped 0x0000000000200000-0x0000000000400000 with 2.00 MiB pages radix-mmu: Mapped 0x0000000000400000-0x0000000002400000 with 2.00 MiB pages (exec) The logic that changes the permissions assumes the linear mapping was split correctly at boot, so it marks the entire 2MB page read-only. That leads to the write fault above. To fix it, the boot time mapping logic needs to consider that if the kernel is running at a non-zero address then _stext is a boundary where it must split the mapping. That leads to the mapping being split correctly, allowing the rodata permission change to take happen correctly, with no spillover: radix-mmu: Mapped 0x0000000000000000-0x0000000000200000 with 2.00 MiB pages (exec) radix-mmu: Mapped 0x0000000000200000-0x0000000000400000 with 2.00 MiB pages radix-mmu: Mapped 0x0000000000400000-0x0000000000500000 with 64.0 KiB pages radix-mmu: Mapped 0x0000000000500000-0x0000000000600000 with 64.0 KiB pages (exec) radix-mmu: Mapped 0x0000000000600000-0x0000000002400000 with 2.00 MiB pages (exec) If the kernel is loaded at a 2MB aligned address, the mapping continues to use 2MB pages as before: radix-mmu: Mapped 0x0000000000000000-0x0000000000200000 with 2.00 MiB pages (exec) radix-mmu: Mapped 0x0000000000200000-0x0000000000400000 with 2.00 MiB pages radix-mmu: Mapped 0x0000000000400000-0x0000000002c00000 with 2.00 MiB pages (exec) radix-mmu: Mapped 0x0000000002c00000-0x0000000100000000 with 2.00 MiB pages Fixes: c55d7b5e6426 ("powerpc: Remove STRICT_KERNEL_RWX incompatibility with RELOCATABLE") Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20230110124753.1325426-1-mpe@ellerman.id.au
2023-01-31powerpc/kexec_file: Fix division by zero in extra size estimationMichael Ellerman
In kexec_extra_fdt_size_ppc64() there's logic to estimate how much extra space will be needed in the device tree for some memory related properties. That logic uses the size of RAM divided by drmem_lmb_size() to do the estimation. However drmem_lmb_size() can be zero if the machine has no hotpluggable memory configured, which is the case when booting with qemu and no maxmem=x parameter is passed (the default). The division by zero is reported by UBSAN, and can also lead to an overflow and a warning from kvmalloc, and kdump kernel loading fails: WARNING: CPU: 0 PID: 133 at mm/util.c:596 kvmalloc_node+0x15c/0x160 Modules linked in: CPU: 0 PID: 133 Comm: kexec Not tainted 6.2.0-rc5-03455-g07358bd97810 #223 Hardware name: IBM pSeries (emulated by qemu) POWER9 (raw) 0x4e1200 0xf000005 of:SLOF,git-dd0dca pSeries NIP: c00000000041ff4c LR: c00000000041fe58 CTR: 0000000000000000 REGS: c0000000096ef750 TRAP: 0700 Not tainted (6.2.0-rc5-03455-g07358bd97810) MSR: 800000000282b033 <SF,VEC,VSX,EE,FP,ME,IR,DR,RI,LE> CR: 24248242 XER: 2004011e CFAR: c00000000041fed0 IRQMASK: 0 ... NIP kvmalloc_node+0x15c/0x160 LR kvmalloc_node+0x68/0x160 Call Trace: kvmalloc_node+0x68/0x160 (unreliable) of_kexec_alloc_and_setup_fdt+0xb8/0x7d0 elf64_load+0x25c/0x4a0 kexec_image_load_default+0x58/0x80 sys_kexec_file_load+0x5c0/0x920 system_call_exception+0x128/0x330 system_call_vectored_common+0x15c/0x2ec To fix it, skip the calculation if drmem_lmb_size() is zero. Fixes: 2377c92e37fe ("powerpc/kexec_file: fix FDT size estimation for kdump kernel") Cc: stable@vger.kernel.org # v5.12+ Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20230130014707.541110-1-mpe@ellerman.id.au
2023-01-31powerpc/imc-pmu: Revert nest_init_lock to being a mutexMichael Ellerman
The recent commit 76d588dddc45 ("powerpc/imc-pmu: Fix use of mutex in IRQs disabled section") fixed warnings (and possible deadlocks) in the IMC PMU driver by converting the locking to use spinlocks. It also converted the init-time nest_init_lock to a spinlock, even though it's not used at runtime in IRQ disabled sections or while holding other spinlocks. This leads to warnings such as: BUG: sleeping function called from invalid context at include/linux/percpu-rwsem.h:49 in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 1, name: swapper/0 preempt_count: 1, expected: 0 CPU: 7 PID: 1 Comm: swapper/0 Not tainted 6.2.0-rc2-14719-gf12cd06109f4-dirty #1 Hardware name: Mambo,Simulated-System POWER9 0x4e1203 opal:v6.6.6 PowerNV Call Trace: dump_stack_lvl+0x74/0xa8 (unreliable) __might_resched+0x178/0x1a0 __cpuhp_setup_state+0x64/0x1e0 init_imc_pmu+0xe48/0x1250 opal_imc_counters_probe+0x30c/0x6a0 platform_probe+0x78/0x110 really_probe+0x104/0x420 __driver_probe_device+0xb0/0x170 driver_probe_device+0x58/0x180 __driver_attach+0xd8/0x250 bus_for_each_dev+0xb4/0x140 driver_attach+0x34/0x50 bus_add_driver+0x1e8/0x2d0 driver_register+0xb4/0x1c0 __platform_driver_register+0x38/0x50 opal_imc_driver_init+0x2c/0x40 do_one_initcall+0x80/0x360 kernel_init_freeable+0x310/0x3b8 kernel_init+0x30/0x1a0 ret_from_kernel_thread+0x5c/0x64 Fix it by converting nest_init_lock back to a mutex, so that we can call sleeping functions while holding it. There is no interaction between nest_init_lock and the runtime spinlocks used by the actual PMU routines. Fixes: 76d588dddc45 ("powerpc/imc-pmu: Fix use of mutex in IRQs disabled section") Tested-by: Kajol Jain<kjain@linux.ibm.com> Reviewed-by: Kajol Jain<kjain@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20230130014401.540543-1-mpe@ellerman.id.au
2023-01-30powerpc/64: Fix perf profiling asynchronous interrupt handlersNicholas Piggin
Interrupt entry sets the soft mask to IRQS_ALL_DISABLED to match the hard irq disabled state. So when should_hard_irq_enable() returns true because we want PMI interrupts in irq handlers, MSR[EE] is enabled but PMIs just get soft-masked. Fix this by clearing IRQS_PMI_DISABLED before enabling MSR[EE]. This also tidies some of the warnings, no need to duplicate them in both should_hard_irq_enable() and do_hard_irq_enable(). Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20230121100156.2824054-1-npiggin@gmail.com
2023-01-30powerpc/64s: Fix local irq disable when PMIs are disabledNicholas Piggin
When PMI interrupts are soft-masked, local_irq_save() will clear the PMI mask bit, allowing PMIs in and causing a race condition. This causes a deadlock in native_hpte_insert via hash_preload, which depends on PMIs being disabled since commit 8b91cee5eadd ("powerpc/64s/hash: Make hash faults work in NMI context"). native_hpte_insert calls local_irq_save(). It's possible the lpar hash code is also affected when tracing is enabled because __trace_hcall_entry() calls local_irq_save(). Fix this by making arch_local_irq_save() _or_ the IRQS_DISABLED bit into the mask. This was found with the stress_hpt option with a kbuild workload running together with `perf record -g`. Fixes: f442d004806e ("powerpc/64s: Add support to mask perf interrupts and replay them") Fixes: 8b91cee5eadd ("powerpc/64s/hash: Make hash faults work in NMI context") Signed-off-by: Nicholas Piggin <npiggin@gmail.com> [mpe: Just take the fix without the new warning] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20230121095352.2823517-1-npiggin@gmail.com
2023-01-30powerpc/pci: Enable PPC_PCI_BUS_NUM_DOMAIN_DEPENDENT by defaultPali Rohár
It makes sense to enable CONFIG_PPC_PCI_BUS_NUM_DOMAIN_DEPENDENT by default (when possible by dependencies) to take advantages of all 256 PCI buses on each PCI domain, like it is already on all other kernel architectures. Fixes: 566356813082 ("powerpc/pci: Add config option for using all 256 PCI buses") Signed-off-by: Pali Rohár <pali@kernel.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20230128133459.32123-1-pali@kernel.org
2023-01-30powerpc/64: Don't recurse irq replayNicholas Piggin
Interrupt handlers called by soft-pending irq replay code can run softirqs, softirq replay enables and disables local irqs, which allows interrupts to come in including soft-masked interrupts, and it can cause pending irqs to be replayed again. That makes the soft irq replay state machine and possible races more complicated and fragile than it needs to be. Use irq_enter/irq_exit around irq replay to prevent softirqs running while interrupts are being replayed. Softirqs will now be run at the irq_exit() call after all the irq replaying is done. This prevents irqs being replayed while irqs are being replayed, and should hopefully make things simpler and easier to think about and debug. A new PACA_IRQ_REPLAYING is added to prevent asynchronous interrupt handlers hard-enabling EE while pending irqs are being replayed, because that causes new pending irqs to arrive which is also a complexity. This means pending irqs won't be profiled quite so well because perf irqs can't be taken. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20230121102618.2824429-1-npiggin@gmail.com
2023-01-30powerpc: Check !irq instead of irq == NO_IRQ and remove NO_IRQChristophe Leroy
NO_IRQ is a relic from the old days. It is not used anymore in core functions. By the way, function irq_of_parse_and_map() returns value 0 on error. In some drivers, NO_IRQ is erroneously used to check the return of irq_of_parse_and_map(). It is not a real bug today because the only architectures using the drivers being fixed by this patch define NO_IRQ as 0, but there are architectures which define NO_IRQ as -1. If one day those architectures start using the non fixed drivers, there will be a problem. Long time ago Linus advocated for not using NO_IRQ, see https://lore.kernel.org/all/Pine.LNX.4.64.0511211150040.13959@g5.osdl.org He re-iterated the same view recently in https://lore.kernel.org/all/CAHk-=wg2Pkb9kbfbstbB91AJA2SF6cySbsgHG-iQMq56j3VTcA@mail.gmail.com So test !irq instead of tesing irq == NO_IRQ. All other usage of NO_IRQ for powerpc were removed in previous cycles so the time has come to remove NO_IRQ completely for powerpc. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/4b8d4f96140af01dec3a3330924dda8b2451c316.1674476798.git.christophe.leroy@csgroup.eu
2023-01-30powerpc/rtas: upgrade internal arch spinlocksNathan Lynch
At the time commit f97bb36f705d ("powerpc/rtas: Turn rtas lock into a raw spinlock") was written, the spinlock lockup detection code called __delay(), which will not make progress if the timebase is not advancing. Since the interprocessor timebase synchronization sequence for chrp, cell, and some now-unsupported Power models can temporarily freeze the timebase through an RTAS function (freeze-time-base), the lock that serializes most RTAS calls was converted to arch_spinlock_t to prevent kernel hangs in the lockup detection code. However, commit bc88c10d7e69 ("locking/spinlock/debug: Remove spinlock lockup detection code") removed that inconvenient property from the lock debug code several years ago. So now it should be safe to reintroduce generic locks into the RTAS support code, primarily to increase lockdep coverage. Making rtas_lock a spinlock_t would violate lock type nesting rules because it can be acquired while holding raw locks, e.g. pci_lock and irq_desc->lock. So convert it to raw_spinlock_t. There's no apparent reason not to upgrade timebase_lock as well. Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20230124140448.45938-5-nathanl@linux.ibm.com
2023-01-30powerpc/rtas: remove lock and args fields from global rtas structNathan Lynch
Only code internal to the RTAS subsystem needs access to the central lock and parameter block. Remove these from the globally visible 'rtas' struct and make them file-static in rtas.c. Some changed lines in rtas_call() lack appropriate spacing around operators and cause checkpatch errors; fix these as well. Suggested-by: Laurent Dufour <ldufour@linux.ibm.com> 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/20230124140448.45938-4-nathanl@linux.ibm.com
2023-01-30powerpc/rtas: make all exports GPLNathan Lynch
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
2023-01-30powerpc/rtas: Drop unused export symbolsMichael Ellerman
Some RTAS symbols are never used by modular code, drop their exports. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Reviewed-by: Nathan Lynch <nathanl@linux.ibm.com> Link: https://lore.kernel.org/r/20230127111231.84294-1-mpe@ellerman.id.au
2023-01-30powerpc/rtas: unexport 'rtas' symbolNathan Lynch
No modular code needs access to the 'rtas' struct, so remove the symbol export. Suggested-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20230124140448.45938-2-nathanl@linux.ibm.com
2023-01-30powerpc/boot: Don't always pass -mcpu=powerpc when building 32-bit uImagePali Rohár
When CONFIG_TARGET_CPU is specified then pass its value to the compiler -mcpu option. This fixes following build error when building kernel with powerpc e500 SPE capable cross compilers: BOOTAS arch/powerpc/boot/crt0.o powerpc-linux-gnuspe-gcc: error: unrecognized argument in option ‘-mcpu=powerpc’ powerpc-linux-gnuspe-gcc: note: valid arguments to ‘-mcpu=’ are: 8540 8548 native make[1]: *** [arch/powerpc/boot/Makefile:231: arch/powerpc/boot/crt0.o] Error 1 Similar change was already introduced for the main powerpc Makefile in commit 446cda1b21d9 ("powerpc/32: Don't always pass -mcpu=powerpc to the compiler"). Fixes: 40a75584e526 ("powerpc/boot: Build wrapper for an appropriate CPU") Cc: stable@vger.kernel.org # v5.19+ Signed-off-by: Pali Rohár <pali@kernel.org> Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/2ae3ae5887babfdacc34435bff0944b3f336100a.1674632329.git.christophe.leroy@csgroup.eu
2023-01-30powerpc/64: Set default CPU in KconfigChristophe Leroy
Since commit 0069f3d14e7a ("powerpc/64e: Tie PPC_BOOK3E_64 to PPC_E500MC"), the only possible BOOK3E/64 are E500, so no need of a default CPU over the E5500. When the user selects book3e, they must have an e500 compatible compiler, and it won't work anymore with the default -mcpu=power64, see commit d6b551b8f90c ("powerpc/64e: Fix build failure with GCC 12 (unrecognized opcode: `wrteei')"). For book3s/64, replace GENERIC_CPU by POWERPC64_CPU to match the PPC32 POWERPC_CPU, and set a default mpcu value in Kconfig directly. When a user selects a particular CPU, they must ensure the compiler has the requested capability. Therefore, remove hidden fallback, instead offer user the possibility to say they want to use the toolchain default. Fixes: d6b551b8f90c ("powerpc/64e: Fix build failure with GCC 12 (unrecognized opcode: `wrteei')") Reported-by: Pali Rohár <pali@kernel.org> Tested-by: Pali Rohár <pali@kernel.org> Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/76c11197b058193dcb8e8b26adffba09cfbdab11.1674632329.git.christophe.leroy@csgroup.eu
2023-01-30powerpc/kvm: Fix unannotated intra-function call warningSathvika Vasireddy
objtool throws the following warning: arch/powerpc/kvm/booke.o: warning: objtool: kvmppc_fill_pt_regs+0x30: unannotated intra-function call Fix the warning by setting the value of 'nip' using the _THIS_IP_ macro, without using an assembly bl/mflr sequence to save the instruction pointer. Reported-by: kernel test robot <lkp@intel.com> Suggested-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Sathvika Vasireddy <sv@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20230128124158.1066251-1-sv@linux.ibm.com
2023-01-30powerpc/85xx: Fix unannotated intra-function call warningSathvika Vasireddy
objtool throws the following warning: arch/powerpc/kernel/head_85xx.o: warning: objtool: .head.text+0x1a6c: unannotated intra-function call Fix the warning by annotating KernelSPE symbol with SYM_FUNC_START_LOCAL and SYM_FUNC_END macros. Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Sathvika Vasireddy <sv@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20230128124138.1066176-1-sv@linux.ibm.com
2023-01-26powerpc/module_64: Fix "expected nop" error on module re-patchingJosh Poimboeuf
When a module with a livepatched function is unloaded and then reloaded, klp attempts to dynamically re-patch it. On ppc64, that fails with the following error: module_64: livepatch_nfsd: Expected nop after call, got e8410018 at e_show+0x60/0x548 [livepatch_nfsd] livepatch: failed to initialize patch 'livepatch_nfsd' for module 'nfsd' (-8) livepatch: patch 'livepatch_nfsd' failed for module 'nfsd', refusing to load module 'nfsd' The error happens because the restore r2 instruction had already previously been written into the klp module's replacement function when the original function was patched the first time. So the instruction wasn't a nop as expected. When the restore r2 instruction has already been patched in, detect that and skip the warning and the instruction write. Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org> Reviewed-by: Petr Mladek <pmladek@suse.com> Acked-by: Song Liu <song@kernel.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/2f6329ffd9674df6ff57e03edeb2ca54414770ab.1674617130.git.jpoimboe@kernel.org
2023-01-26powerpc/module_64: Improve restore_r2() return semanticsJosh Poimboeuf
restore_r2() returns 1 on success, which is surprising for a non-boolean function. Change it to return 0 on success and -errno on error to match kernel coding convention. Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org> Reviewed-by: Petr Mladek <pmladek@suse.com> Acked-by: Song Liu <song@kernel.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/15baf76c271a0ae09f7b8556e50f2b4251e7049d.1674617130.git.jpoimboe@kernel.org
2023-01-12powerpc/64s/hash: Make stress_hpt_timer_fn() staticYang Yingliang
stress_hpt_timer_fn() is only used in hash_utils.c, make it static. Fixes: 6b34a099faa1 ("powerpc/64s/hash: add stress_hpt kernel boot option to increase hash faults") Signed-off-by: Yang Yingliang <yangyingliang@huawei.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20221228093603.3166599-1-yangyingliang@huawei.com
2023-01-11powerpc/imc-pmu: Fix use of mutex in IRQs disabled sectionKajol Jain
Current imc-pmu code triggers a WARNING with CONFIG_DEBUG_ATOMIC_SLEEP and CONFIG_PROVE_LOCKING enabled, while running a thread_imc event. Command to trigger the warning: # perf stat -e thread_imc/CPM_CS_FROM_L4_MEM_X_DPTEG/ sleep 5 Performance counter stats for 'sleep 5': 0 thread_imc/CPM_CS_FROM_L4_MEM_X_DPTEG/ 5.002117947 seconds time elapsed 0.000131000 seconds user 0.001063000 seconds sys Below is snippet of the warning in dmesg: BUG: sleeping function called from invalid context at kernel/locking/mutex.c:580 in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 2869, name: perf-exec preempt_count: 2, expected: 0 4 locks held by perf-exec/2869: #0: c00000004325c540 (&sig->cred_guard_mutex){+.+.}-{3:3}, at: bprm_execve+0x64/0xa90 #1: c00000004325c5d8 (&sig->exec_update_lock){++++}-{3:3}, at: begin_new_exec+0x460/0xef0 #2: c0000003fa99d4e0 (&cpuctx_lock){-...}-{2:2}, at: perf_event_exec+0x290/0x510 #3: c000000017ab8418 (&ctx->lock){....}-{2:2}, at: perf_event_exec+0x29c/0x510 irq event stamp: 4806 hardirqs last enabled at (4805): [<c000000000f65b94>] _raw_spin_unlock_irqrestore+0x94/0xd0 hardirqs last disabled at (4806): [<c0000000003fae44>] perf_event_exec+0x394/0x510 softirqs last enabled at (0): [<c00000000013c404>] copy_process+0xc34/0x1ff0 softirqs last disabled at (0): [<0000000000000000>] 0x0 CPU: 36 PID: 2869 Comm: perf-exec Not tainted 6.2.0-rc2-00011-g1247637727f2 #61 Hardware name: 8375-42A POWER9 0x4e1202 opal:v7.0-16-g9b85f7d961 PowerNV Call Trace: dump_stack_lvl+0x98/0xe0 (unreliable) __might_resched+0x2f8/0x310 __mutex_lock+0x6c/0x13f0 thread_imc_event_add+0xf4/0x1b0 event_sched_in+0xe0/0x210 merge_sched_in+0x1f0/0x600 visit_groups_merge.isra.92.constprop.166+0x2bc/0x6c0 ctx_flexible_sched_in+0xcc/0x140 ctx_sched_in+0x20c/0x2a0 ctx_resched+0x104/0x1c0 perf_event_exec+0x340/0x510 begin_new_exec+0x730/0xef0 load_elf_binary+0x3f8/0x1e10 ... do not call blocking ops when !TASK_RUNNING; state=2001 set at [<00000000fd63e7cf>] do_nanosleep+0x60/0x1a0 WARNING: CPU: 36 PID: 2869 at kernel/sched/core.c:9912 __might_sleep+0x9c/0xb0 CPU: 36 PID: 2869 Comm: sleep Tainted: G W 6.2.0-rc2-00011-g1247637727f2 #61 Hardware name: 8375-42A POWER9 0x4e1202 opal:v7.0-16-g9b85f7d961 PowerNV NIP: c000000000194a1c LR: c000000000194a18 CTR: c000000000a78670 REGS: c00000004d2134e0 TRAP: 0700 Tainted: G W (6.2.0-rc2-00011-g1247637727f2) MSR: 9000000000021033 <SF,HV,ME,IR,DR,RI,LE> CR: 48002824 XER: 00000000 CFAR: c00000000013fb64 IRQMASK: 1 The above warning triggered because the current imc-pmu code uses mutex lock in interrupt disabled sections. The function mutex_lock() internally calls __might_resched(), which will check if IRQs are disabled and in case IRQs are disabled, it will trigger the warning. Fix the issue by changing the mutex lock to spinlock. Fixes: 8f95faaac56c ("powerpc/powernv: Detect and create IMC device") Reported-by: Michael Petlan <mpetlan@redhat.com> Reported-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Kajol Jain <kjain@linux.ibm.com> [mpe: Fix comments, trim oops in change log, add reported-by tags] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20230106065157.182648-1-kjain@linux.ibm.com
2023-01-11powerpc/boot: Fix incorrect version calculation issue in ld_versionOjaswin Mujoo
The ld_version() function computes the wrong version value for certain ld versions such as the following: $ ld --version GNU ld (GNU Binutils; SUSE Linux Enterprise 15) 2.37.20211103-150100.7.37 For input 2.37.20211103, the value computed is 202348030000 which is higher than the value for a later version like 2.39.0, which is 23900000. This issue was highlighted because with the above ld version, the powerpc kernel build started failing with ld error: "unrecognized option --no-warn-rwx-segments". This was caused due to the recent commit 579aee9fc594 ("powerpc: suppress some linker warnings in recent linker versions") which added the --no-warn-rwx-segments linker flag if the ld version is greater than 2.39. Due to the bug in ld_version(), ld version 2.37.20111103 is wrongly calculated to be greater than 2.39 and the unsupported flag is added. To fix it, if version is of the form x.y.z and length(z) == 8, then most probably it is a date [yyyymmdd] commonly used for release snapshots and not an actual new version. Hence, ignore the date part replacing it with 0. Fixes: 579aee9fc594 ("powerpc: suppress some linker warnings in recent linker versions") Signed-off-by: Ojaswin Mujoo <ojaswin@linux.ibm.com> [mpe: Tweak change log wording/formatting, add Fixes tag] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20230104202437.90039-1-ojaswin@linux.ibm.com
2023-01-11Merge branch 'fixes' into nextMichael Ellerman
Merge our fixes branch to bring in the linker script fixes for older toolchains.
2023-01-06powerpc/vmlinux.lds: Don't discard .commentMichael Ellerman
Although the powerpc linker script mentions .comment in the DISCARD section, that has never actually caused it to be discarded, because the earlier ELF_DETAILS macro (previously STABS_DEBUG) explicitly includes .comment. However commit 99cb0d917ffa ("arch: fix broken BuildID for arm64 and riscv") introduced an earlier use of DISCARD as part of the RO_DATA macro. With binutils < 2.36 that causes the DISCARD directives later in the script to be applied earlier, causing .comment to actually be discarded. It's confusing to explicitly include and discard .comment, and even more so if the behaviour depends on the toolchain version. So don't discard .comment in order to maintain the existing behaviour in all cases. Fixes: 83a092cf95f2 ("powerpc: Link warning for orphan sections") Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20230105132349.384666-3-mpe@ellerman.id.au
2023-01-06powerpc/vmlinux.lds: Don't discard .rela* for relocatable buildsMichael Ellerman
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 99cb0d917ffa ("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: 99cb0d917ffa ("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
2023-01-06powerpc/vmlinux.lds: Define RUNTIME_DISCARD_EXITMichael Ellerman
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 99cb0d917ffa ("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: 99cb0d917ffa ("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
2023-01-01Linux 6.2-rc2v6.2-rc2Linus Torvalds
2023-01-01Merge tag 'perf_urgent_for_v6.2_rc2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf fixes from Borislav Petkov: - Pass only an initialized perf event attribute to the LSM hook - Fix a use-after-free on the perf syscall's error path - A potential integer overflow fix in amd_core_pmu_init() - Fix the cgroup events tracking after the context handling rewrite - Return the proper value from the inherit_event() function on error * tag 'perf_urgent_for_v6.2_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf/core: Call LSM hook after copying perf_event_attr perf: Fix use-after-free in error path perf/x86/amd: fix potential integer overflow on shift of a int perf/core: Fix cgroup events tracking perf core: Return error pointer if inherit_event() fails to find pmu_ctx
2023-01-01Merge tag 'x86_urgent_for_v6.2_rc2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Borislav Petkov: - Two fixes to correct how kprobes handles INT3 now that they're added by other functionality like the rethunks and not only kgdb - Remove __init section markings of two functions which are referenced by a function in the .text section * tag 'x86_urgent_for_v6.2_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/kprobes: Fix optprobe optimization check with CONFIG_RETHUNK x86/kprobes: Fix kprobes instruction boudary check with CONFIG_RETHUNK x86/calldepth: Fix incorrect init section references