- 05 May, 2022 18 commits
-
-
Nicholas Piggin authored
emulate_step() instruction emulation including sc instruction emulation initially appeared in xmon. It was then moved into sstep.c where kprobes could use it too, and later hw_breakpoint and uprobes started to use it. Until uprobes, the only instruction emulation users were for kernel mode instructions. - xmon only steps / breaks on kernel addresses. - kprobes is kernel only. - hw_breakpoint only emulates kernel instructions, single steps user. At one point, there was support for the kernel to execute sc instructions, although that is long removed and it's not clear whether there were any in-tree users. So system call emulation is not required by the above users. uprobes uses emulate_step and it appears possible to emulate sc instruction in userspace. Userspace system call emulation is broken and it's not clear it ever worked well. The big complication is that userspace takes an interrupt to the kernel to emulate the instruction. The user->kernel interrupt sets up registers and interrupt stack frame expecting to return to userspace, then system call instruction emulation re-directs that stack frame to the kernel, early in the system call interrupt handler. This means the interrupt return code takes the kernel->kernel restore path, which does not restore everything as the system call interrupt handler would expect coming from userspace. regs->iamr appears to get lost for example, because the kernel->kernel return does not restore the user iamr. Accounting such as irqflags tracing and CPU accounting does not get flipped back to user mode as the system call handler expects, so those appear to enter the kernel twice without returning to userspace. These things may be individually fixable with various complication, but it is a big complexity for unclear real benefit. Furthermore, it is not possible to single step a system call instruction since it causes an interrupt. As such, a separate patch disables probing on system call instructions. This patch removes system call emulation and disables stepping system calls. Signed-off-by:
Nicholas Piggin <npiggin@gmail.com> [minor commit log edit, and also get rid of '#ifdef CONFIG_PPC64'] Signed-off-by:
Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by:
Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/a412e3b3791ed83de18704c8d90f492e7a0049c0.1648648712.git.naveen.n.rao@linux.vnet.ibm.com
-
Naveen N. Rao authored
Per the ISA, a Trace interrupt is not generated for: - [h|u]rfi[d] - rfscv - sc, scv, and Trap instructions that trap - Power-Saving Mode instructions - other instructions that cause interrupts (other than Trace interrupts) - the first instructions of any interrupt handler (applies to Branch and Single Step tracing; CIABR matches may still occur) - instructions that are emulated by software Add a helper to check for instructions belonging to the first four categories above and to reject kprobes, uprobes and xmon breakpoints on such instructions. We reject probing on instructions belonging to these categories across all ISA versions and across both BookS and BookE. For trap instructions, we can't know in advance if they can cause a trap, and there is no good reason to allow probing on those. Also, uprobes already refuses to probe trap instructions and kprobes does not allow probes on trap instructions used for kernel warnings and bugs. As such, stop allowing any type of probes/breakpoints on trap instruction across uprobes, kprobes and xmon. For some of the fp/altivec instructions that can generate an interrupt and which we emulate in the kernel (altivec assist, for example), we check and turn off single stepping in emulate_single_step(). Instructions generating a DSI are restarted and single stepping normally completes once the instruction is completed. In uprobes, if a single stepped instruction results in a non-fatal signal to be delivered to the task, such signals are "delayed" until after the instruction completes. For fatal signals, single stepping is cancelled and the instruction restarted in-place so that core dump captures proper addresses. In kprobes, we do not allow probes on instructions having an extable entry and we also do not allow probing interrupt vectors. Signed-off-by:
-
Naveen N. Rao authored
Some of the primary opcodes are duplicated. Remove those, and sort the rest of the primary opcodes to make it easy to read. Signed-off-by:
-
Julia Lawall authored
Various spelling mistakes in comments. Detected with the help of Coccinelle. Signed-off-by:
Julia Lawall <Julia.Lawall@inria.fr> Reviewed-by:
Joel Stanley <joel@jms.id.au> Signed-off-by:
-
Alexey Kardashevskiy authored
So far the RELACOUNT tag from the ELF header was containing the exact number of R_PPC_RELATIVE/R_PPC64_RELATIVE relocations. However the LLVM's recent change [1] make it equal-or-less than the actual number which makes it useless. This replaces RELACOUNT in zImage loader with a pair of RELASZ and RELAENT. The vmlinux relocation code is fixed in commit d7997691 ("powerpc/64: Add UADDR64 relocation support"). To make it more future proof, this walks through the entire .rela.dyn section instead of assuming that the section is sorter by a relocation type. Unlike d7997691, this does not add unaligned UADDR/UADDR64 relocations as we are likely not to see those in practice - the zImage is small and very arch specific so there is a smaller chance that some generic feature (such as PRINK_INDEX) triggers unaligned relocations. [1] https://github.com/llvm/llvm-project/commit/da0e5b885b25cf4Signed-off-by:
Alexey Kardashevskiy <aik@ozlabs.ru> Signed-off-by:
-
Christophe Leroy authored
arch_randomize_brk() is only needed for hash on book3s/64, for other platforms the one provided by the default mmap layout is good enough. Move it to hash_utils.c and use randomize_page() like the generic one. And properly opt out the radix case instead of making an assumption on mmu_highuser_ssize. Also change to a 32M range like most other architectures instead of 8M. Signed-off-by:
Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by:
-
Christophe Leroy authored
Select CONFIG_ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT and remove arch/powerpc/mm/mmap.c This change reuses the generic framework added by commit 67f3977f ("arm64, mm: move generic mmap layout functions to mm") without any functional change. Comparison between powerpc implementation and the generic one: - mmap_is_legacy() is identical. - arch_mmap_rnd() does exactly the same allthough it's written slightly differently. - MIN_GAP and MAX_GAP are identical. - mmap_base() does the same but uses STACK_RND_MASK which provides the same values as stack_maxrandom_size(). - arch_pick_mmap_layout() is identical. Signed-off-by:
-
Christophe Leroy authored
Do like most other architectures and provide randomisation also to "legacy" memory mappings, by adding the random factor to mm->mmap_base in arch_pick_mmap_layout(). See commit 8b8addf8 ("x86/mm/32: Enable full randomization on i386 and X86_32") for all explanations and benefits of that mmap randomisation. At the moment, slice_find_area_bottomup() doesn't use mm->mmap_base but uses the fixed TASK_UNMAPPED_BASE instead. slice_find_area_bottomup() being used as a fallback to slice_find_area_topdown(), it can't use mm->mmap_base directly. Instead of always using TASK_UNMAPPED_BASE as base address, leave it to the caller. When called from slice_find_area_topdown() TASK_UNMAPPED_BASE is used. Otherwise mm->mmap_base is used. Signed-off-by:
-
Christophe Leroy authored
hugetlb_get_unmapped_area() is now identical to the generic version if only RADIX is enabled, so move it to slice.c and let it fallback on the generic one when HASH MMU is not compiled in. Do the same with arch_get_unmapped_area() and arch_get_unmapped_area_topdown(). Signed-off-by:
-
Christophe Leroy authored
Use the generic version of arch_hugetlb_get_unmapped_area() which is now available at all time. Signed-off-by:
-
Christophe Leroy authored
Use the generic version of arch_get_unmapped_area() which is now available at all time instead of its copy radix__arch_get_unmapped_area() To allow that for PPC64, add arch_get_mmap_base() and arch_get_mmap_end() macros. Instead of setting mm->get_unmapped_area() to either arch_get_unmapped_area() or generic_get_unmapped_area(), always set it to arch_get_unmapped_area() and call generic_get_unmapped_area() from there when radix is enabled. Do the same with radix__arch_get_unmapped_area_topdown() Signed-off-by:
-
Christophe Leroy authored
CONFIG_PPC_MM_SLICES is always selected by hash book3s/64. CONFIG_PPC_MM_SLICES is never selected by other platforms. Remove it. Signed-off-by:
-
Christophe Leroy authored
Since commit 555904d0 ("powerpc/8xx: MM_SLICE is not needed anymore") only book3s/64 selects CONFIG_PPC_MM_SLICES. Move slice.c into mm/book3s64/ Move necessary stuff in asm/book3s/64/slice.h and remove asm/slice.h Signed-off-by:
-
Christophe Leroy authored
vma_mmu_pagesize() is only required for slices, otherwise there is a generic weak version doing the exact same thing. Move it to slice.c Signed-off-by:
-
Christophe Leroy authored
Powerpc needs flags and len to make decision on arch_get_mmap_end(). So add them as parameters to arch_get_mmap_end(). Signed-off-by:
Catalin Marinas <catalin.marinas@arm.com> Acked-by:
Andrew Morton <akpm@linux-foundation.org> Signed-off-by:
-
Christophe Leroy authored
Unlike most architectures, powerpc can only define at runtime if it is going to use the generic arch_get_unmapped_area() or not. Today, powerpc has a copy of the generic arch_get_unmapped_area() because when selection HAVE_ARCH_UNMAPPED_AREA the generic arch_get_unmapped_area() is not available. Rename it generic_get_unmapped_area() and make it independent of HAVE_ARCH_UNMAPPED_AREA. Do the same for arch_get_unmapped_area_topdown() versus HAVE_ARCH_UNMAPPED_AREA_TOPDOWN. Do the same for hugetlb_get_unmapped_area() versus HAVE_ARCH_HUGETLB_UNMAPPED_AREA. Signed-off-by:
-
Christophe Leroy authored
Commit e7142bf5 ("arm64, mm: make randomization selected by generic topdown mmap layout") introduced a default version of arch_randomize_brk() provided when CONFIG_ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT is selected. powerpc could select CONFIG_ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT but needs to provide its own arch_randomize_brk(). In order to allow that, define generic version of arch_randomize_brk() as a __weak symbol. Signed-off-by:
-
Michael Ellerman authored
Merge master into next, to bring in commit 5f24d5a5 ("mm, hugetlb: allow for "high" userspace addresses"), which is needed as a prerequisite for the series converting powerpc to the generic mmap logic.
-
- 04 May, 2022 22 commits
-
-
YueHaibing authored
pseries_eeh_init_edev() is used exclusively in eeh_pseries.c, make it static and remove unused inline function. pseries_eeh_init_edev_recursive() is only called from files build wich CONFIG_HOTPLUG_PCI_RPA which depends on CONFIG_PSERIES and CONFIG_EEH, so can remove the unused inline version. Suggested-by:
YueHaibing <yuehaibing@huawei.com> Signed-off-by:
-
Michael Ellerman authored
Replace open-coded for loop with for_each_property_of_node(). Reported-by:
Jiapeng Chong <jiapeng.chong@linux.alibaba.com> Signed-off-by:
-
Randy Dunlap authored
__setup() handlers should return 1 to obsolete_checksetup() in init/main.c to indicate that the boot option has been handled. A return of 0 causes the boot option/value to be listed as an Unknown kernel parameter and added to init's (limited) argument or environment strings. Also, error return codes don't mean anything to obsolete_checksetup() -- only non-zero (usually 1) or zero. So return 1 from cpm_powersave_off(). Fixes: d164f6d4 ("powerpc/4xx: Add suspend and idle support") Reported-by:
Igor Zhbanov <izh1979@gmail.com> Signed-off-by:
Randy Dunlap <rdunlap@infradead.org> Signed-off-by:
-
Randy Dunlap authored
__setup() handlers should return 1 to obsolete_checksetup() in init/main.c to indicate that the boot option has been handled. A return of 0 causes the boot option/value to be listed as an Unknown kernel parameter and added to init's (limited) argument or environment strings. Also, error return codes don't mean anything to obsolete_checksetup() -- only non-zero (usually 1) or zero. So return 1 from powersave_off(). Fixes: 302eca18 ("[POWERPC] cell: use ppc_md->power_save instead of cbe_idle_loop") Reported-by:
-
Wang Qing authored
do_div() does a 64-by-32 division, the 2nd parameter is a u32. gbp->ipb_freq is already a u32, there's no need to transform it to u64 before passing it to do_div(). Signed-off-by:
Wang Qing <wangqing@vivo.com> Signed-off-by:
-
Russell Currey authored
Signed-off-by:
Russell Currey <ruscur@russell.cc> Signed-off-by:
-
Zou Wei authored
Use for_each_child_of_node() macro instead of open coding it. Reported-by:
Hulk Robot <hulkci@huawei.com> Signed-off-by:
Zou Wei <zou_wei@huawei.com> Signed-off-by:
-
Christophe Leroy authored
Make tlbcam_addrs[] static. Declare TLBCAM[] in mm/mmu_decl.h And use NULL instead of 0 as pointer when calling restore_to_as0(). Reported-by:
kernel test robot <lkp@intel.com> Signed-off-by:
-
YueHaibing authored
commit 2341964e ("powerpc/kuap: Remove __kuap_assert_locked()") left behind this one, remove it. Signed-off-by:
-
YueHaibing authored
commit 441c19c8 ("powerpc/kvm/book3s_hv: Rework the secondary inhibit code") left behind this, so can remove it. Signed-off-by:
Daniel Axtens <dja@axtens.net> Signed-off-by:
-
maqiang authored
These one line of code don't meet the kernel coding style, so remove the redundant space. Signed-off-by:
maqiang <maqianga@uniontech.com> Signed-off-by:
-
Magali Lemes authored
When CONFIG_PPC64 is set and CONFIG_ALTIVEC is not the following build failures occur: drivers/gpu/drm/amd/amdgpu/../display/amdgpu_dm/dc_fpu.c: In function 'dc_fpu_begin': >> drivers/gpu/drm/amd/amdgpu/../display/amdgpu_dm/dc_fpu.c:61:17: error: implicit declaration of function 'enable_kernel_altivec'; did you mean 'enable_kernel_vsx'? [-Werror=implicit-function-declaration] 61 | enable_kernel_altivec(); | ^~~~~~~~~~~~~~~~~~~~~ | enable_kernel_vsx drivers/gpu/drm/amd/amdgpu/../display/amdgpu_dm/dc_fpu.c: In function 'dc_fpu_end': >> drivers/gpu/drm/amd/amdgpu/../display/amdgpu_dm/dc_fpu.c:89:17: error: implicit declaration of function 'disable_kernel_altivec'; did you mean 'disable_kernel_vsx'? [-Werror=implicit-function-declaration] 89 | disable_kernel_altivec(); | ^~~~~~~~~~~~~~~~~~~~~~ | disable_kernel_vsx cc1: some warnings being treated as errors This commit adds stub instances of both enable_kernel_altivec() and disable_kernel_altivec() the same way as done in commit bd737588 regarding enable_kernel_vsx() and disable_kernel_vsx(). Reported-by:Magali Lemes <magalilemes00@gmail.com> Signed-off-by:
-
Yang Li authored
Fix the following coccicheck warnings: ./drivers/macintosh/via-cuda.c:240:16-17: WARNING comparing pointer to 0 ./drivers/macintosh/via-cuda.c:243:16-17: WARNING comparing pointer to 0, suggest !E ./drivers/macintosh/via-cuda.c:521:23-24: WARNING comparing pointer to 0 Reported-by:
Abaci Robot <abaci@linux.alibaba.com> Signed-off-by:
Yang Li <yang.lee@linux.alibaba.com> Signed-off-by:
-
Jiapeng Chong authored
Clean the following coccicheck warning: ./arch/powerpc/kernel/fadump.c:1291:34-35: WARNING opportunity for swap(). Reported-by:
-
Minghao Chi authored
Return the value from i2c_add_driver() directly instead of storing it in another redundant variable. Reported-by:
Zeal Robot <zealci@zte.com.cn> Signed-off-by:
Minghao Chi <chi.minghao@zte.com.cn> Signed-off-by:
CGEL ZTE <cgel.zte@gmail.com> Signed-off-by:
-
Xiang wangx authored
Static variables do not need to be initialised to 0, because compiler will initialise all uninitialised statics to 0. Thus, remove the unneeded initializations. Signed-off-by:
Xiang wangx <wangxiang@cdjrlc.com> Signed-off-by:
-
Yang Guang authored
Use the macro 'swap()' defined in 'include/linux/minmax.h' to avoid opencoding it. Reported-by:
Yang Guang <yang.guang5@zte.com.cn> Signed-off-by:
-
Randy Dunlap authored
Fix typos of 'remaining' and 'those'. Signed-off-by:
-
Qing Wang authored
show() must not use snprintf() when formatting the value to be returned to user space. Fix the following coccicheck warning: drivers/macintosh/ams/ams-core.c:53: WARNING: use scnprintf or sprintf. Use sysfs_emit instead of scnprintf or sprintf makes more sense. Signed-off-by:
-
Sohaib Mohamed authored
Remove repeated words: "the the lowest" and "this this kernel" Signed-off-by:
Sohaib Mohamed <sohaib.amhmd@gmail.com> Acked-by:
Andrew Donnellan <ajd@linux.ibm.com> Signed-off-by:
-
Jing Yangyang authored
Fix the following coccicheck warning: ./drivers/macintosh/smu.c:1089: 11-12: WARNING comparing pointer to 0, suggest !E ./drivers/macintosh/smu.c:1256:11-12: WARNING comparing pointer to 0 Reported-by:
Jing Yangyang <jing.yangyang@zte.com.cn> Signed-off-by:
-
Jason Wang authored
The strlcpy should not be used because it doesn't limit the source length. As linus says, it's a completely useless function if you can't implicitly trust the source string - but that is almost always why people think they should use it! All in all the BSD function will lead some potential bugs. But the strscpy doesn't require reading memory from the src string beyond the specified "count" bytes, and since the return value is easier to error-check than strlcpy()'s. In addition, the implementation is robust to the string changing out from underneath it, unlike the current strlcpy() implementation. Thus, We prefer using strscpy instead of strlcpy. Signed-off-by:
Jason Wang <wangborong@cdjrlc.com> Signed-off-by:
-
