kernel.git/arch/powerpc/kernel/ptrace, branch linux-5.13.y

Merge tag 'powerpc-5.13-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

2021-04-30T19:22:28Z

Pull powerpc updates from Michael Ellerman: - Enable KFENCE for 32-bit. - Implement EBPF for 32-bit. - Convert 32-bit to do interrupt entry/exit in C. - Convert 64-bit BookE to do interrupt entry/exit in C. - Changes to our signal handling code to use user_access_begin/end() more extensively. - Add support for time namespaces (CONFIG_TIME_NS) - A series of fixes that allow us to reenable STRICT_KERNEL_RWX. - Other smaller features, fixes & cleanups. Thanks to Alexey Kardashevskiy, Andreas Schwab, Andrew Donnellan, Aneesh Kumar K.V, Athira Rajeev, Bhaskar Chowdhury, Bixuan Cui, Cédric Le Goater, Chen Huang, Chris Packham, Christophe Leroy, Christopher M. Riedl, Colin Ian King, Dan Carpenter, Daniel Axtens, Daniel Henrique Barboza, David Gibson, Davidlohr Bueso, Denis Efremov, dingsenjie, Dmitry Safonov, Dominic DeMarco, Fabiano Rosas, Ganesh Goudar, Geert Uytterhoeven, Geetika Moolchandani, Greg Kurz, Guenter Roeck, Haren Myneni, He Ying, Jiapeng Chong, Jordan Niethe, Laurent Dufour, Lee Jones, Leonardo Bras, Li Huafei, Madhavan Srinivasan, Mahesh Salgaonkar, Masahiro Yamada, Nathan Chancellor, Nathan Lynch, Nicholas Piggin, Oliver O'Halloran, Paul Menzel, Pu Lehui, Randy Dunlap, Ravi Bangoria, Rosen Penev, Russell Currey, Santosh Sivaraj, Sebastian Andrzej Siewior, Segher Boessenkool, Shivaprasad G Bhat, Srikar Dronamraju, Stephen Rothwell, Thadeu Lima de Souza Cascardo, Thomas Gleixner, Tony Ambardar, Tyrel Datwyler, Vaibhav Jain, Vincenzo Frascino, Xiongwei Song, Yang Li, Yu Kuai, and Zhang Yunkai. * tag 'powerpc-5.13-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (302 commits) powerpc/signal32: Fix erroneous SIGSEGV on RT signal return powerpc: Avoid clang uninitialized warning in __get_user_size_allowed powerpc/papr_scm: Mark nvdimm as unarmed if needed during probe powerpc/kvm: Fix build error when PPC_MEM_KEYS/PPC_PSERIES=n powerpc/kasan: Fix shadow start address with modules powerpc/kernel/iommu: Use largepool as a last resort when !largealloc powerpc/kernel/iommu: Align size for IOMMU_PAGE_SIZE() to save TCEs powerpc/44x: fix spelling mistake in Kconfig "varients" -> "variants" powerpc/iommu: Annotate nested lock for lockdep powerpc/iommu: Do not immediately panic when failed IOMMU table allocation powerpc/iommu: Allocate it_map by vmalloc selftests/powerpc: remove unneeded semicolon powerpc/64s: remove unneeded semicolon powerpc/eeh: remove unneeded semicolon powerpc/selftests: Add selftest to test concurrent perf/ptrace events powerpc/selftests/perf-hwbreak: Add testcases for 2nd DAWR powerpc/selftests/perf-hwbreak: Coalesce event creation code powerpc/selftests/ptrace-hwbreak: Add testcases for 2nd DAWR powerpc/configs: Add IBMVNIC to some 64-bit configs selftests/powerpc: Add uaccess flush test ...

powerpc: remove partial register save logic

2021-04-14T13:04:44Z

All subarchitectures always save all GPRs to pt_regs interrupt frames now. Remove FULL_REGS and associated bits. Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20210316104206.407354-11-npiggin@gmail.com

powerpc/ptrace: Don't return error when getting/setting FP regs without CONFIG_PPC_FPU_REGS

2021-04-01T13:15:37Z

An #ifdef CONFIG_PPC_FPU_REGS is missing in arch_ptrace() leading to the following Oops because [REGSET_FPR] entry is not initialised in native_regsets[]. [ 41.917608] BUG: Unable to handle kernel instruction fetch [ 41.922849] Faulting instruction address: 0xff8fd228 [ 41.927760] Oops: Kernel access of bad area, sig: 11 [#1] [ 41.933089] BE PAGE_SIZE=4K PREEMPT CMPC885 [ 41.940753] Modules linked in: [ 41.943768] CPU: 0 PID: 366 Comm: gdb Not tainted 5.12.0-rc5-s3k-dev-01666-g7aac86a0f057-dirty #4835 [ 41.952800] NIP: ff8fd228 LR: c004d9e0 CTR: ff8fd228 [ 41.957790] REGS: caae9df0 TRAP: 0400 Not tainted (5.12.0-rc5-s3k-dev-01666-g7aac86a0f057-dirty) [ 41.966741] MSR: 40009032 CR: 82004248 XER: 20000000 [ 41.973540] [ 41.973540] GPR00: c004d9b4 caae9eb0 c1b64f60 c1b64520 c0713cd4 caae9eb8 c1bacdfc 00000004 [ 41.973540] GPR08: 00000200 ff8fd228 c1bac700 00001032 28004242 1061aaf4 00000001 106d64a0 [ 41.973540] GPR16: 00000000 00000000 7fa0a774 10610000 7fa0aef9 00000000 10610000 7fa0a538 [ 41.973540] GPR24: 7fa0a580 7fa0a570 c1bacc00 c1b64520 c1bacc00 caae9ee8 00000108 c0713cd4 [ 42.009685] NIP [ff8fd228] 0xff8fd228 [ 42.013300] LR [c004d9e0] __regset_get+0x100/0x124 [ 42.018036] Call Trace: [ 42.020443] [caae9eb0] [c004d9b4] __regset_get+0xd4/0x124 (unreliable) [ 42.026899] [caae9ee0] [c004da94] copy_regset_to_user+0x5c/0xb0 [ 42.032751] [caae9f10] [c002f640] sys_ptrace+0xe4/0x588 [ 42.037915] [caae9f30] [c0011010] ret_from_syscall+0x0/0x28 [ 42.043422] --- interrupt: c00 at 0xfd1f8e4 [ 42.047553] NIP: 0fd1f8e4 LR: 1004a688 CTR: 00000000 [ 42.052544] REGS: caae9f40 TRAP: 0c00 Not tainted (5.12.0-rc5-s3k-dev-01666-g7aac86a0f057-dirty) [ 42.061494] MSR: 0000d032 CR: 48004442 XER: 00000000 [ 42.068551] [ 42.068551] GPR00: 0000001a 7fa0a040 77dad7e0 0000000e 00000170 00000000 7fa0a078 00000004 [ 42.068551] GPR08: 00000000 108deb88 108dda40 106d6010 44004442 1061aaf4 00000001 106d64a0 [ 42.068551] GPR16: 00000000 00000000 7fa0a774 10610000 7fa0aef9 00000000 10610000 7fa0a538 [ 42.068551] GPR24: 7fa0a580 7fa0a570 1078fe00 1078fd70 1078fd70 00000170 0fdd3244 0000000d [ 42.104696] NIP [0fd1f8e4] 0xfd1f8e4 [ 42.108225] LR [1004a688] 0x1004a688 [ 42.111753] --- interrupt: c00 [ 42.114768] Instruction dump: [ 42.117698] XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX [ 42.125443] XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX [ 42.133195] ---[ end trace d35616f22ab2100c ]--- Adding the missing #ifdef is not good because gdb doesn't like getting an error when getting registers. Instead, make ptrace return 0s when CONFIG_PPC_FPU_REGS is not set. Fixes: b6254ced4da6 ("powerpc/signal: Don't manage floating point regs when no FPU") Cc: stable@vger.kernel.org Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/9121a44a2d50ba1af18d8aa5ada06c9a3bea8afd.1617200085.git.christophe.leroy@csgroup.eu

powerpc/ptrace: Convert gpr32_set_common() to user access block

2021-03-26T12:19:43Z

Use user access block in gpr32_set_common() instead of repetitive __get_user() which imply repetitive KUAP open/close. To get it clean, force inlining of the small set of tiny functions called inside the block. Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/bdcb8652c3bb4ab5b8b3bfd08147434be8fc04c9.1615398498.git.christophe.leroy@csgroup.eu

powerpc/ptrace: Remove duplicate check from pt_regs_check()

2021-03-24T03:09:30Z

"offsetof(struct pt_regs, msr) == offsetof(struct user_pt_regs, msr)" checked in pt_regs_check() twice in a row. Remove the second check. Signed-off-by: Denis Efremov Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20210305112807.26299-1-efremov@linux.com

powerpc/64: context tracking remove _TIF_NOHZ

2021-02-08T13:02:12Z

Add context tracking to the system call handler explicitly, and remove _TIF_NOHZ. This improves system call performance when nohz_full is enabled. On a POWER9, gettid scv system call cost on a nohz_full CPU improves from 1129 cycles to 1004 cycles and on a housekeeping CPU from 550 cycles to 430 cycles. Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20210130130852.2952424-31-npiggin@gmail.com

powerpc/ptrace-view: Use pt_regs values instead of thread_struct based one.

2020-12-03T14:01:26Z

We will remove thread.amr/iamr/uamor in a later patch Signed-off-by: Aneesh Kumar K.V Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20201127044424.40686-14-aneesh.kumar@linux.ibm.com

powerpc/signal: Don't manage floating point regs when no FPU

2020-12-03T14:01:11Z

There is no point in copying floating point regs when there is no FPU and MATH_EMULATION is not selected. Create a new CONFIG_PPC_FPU_REGS bool that is selected by CONFIG_MATH_EMULATION and CONFIG_PPC_FPU, and use it to opt out everything related to fp_state in thread_struct. The asm const used only by fpu.S are opted out with CONFIG_PPC_FPU as fpu.S build is conditionnal to CONFIG_PPC_FPU. The following app spends approx 8.1 seconds system time on an 8xx without the patch, and 7.0 seconds with the patch (13.5% reduction). On an 832x, it spends approx 2.6 seconds system time without the patch and 2.1 seconds with the patch (19% reduction). void sigusr1(int sig) { } int main(int argc, char **argv) { int i = 100000; signal(SIGUSR1, sigusr1); for (;i--;) raise(SIGUSR1); exit(0); } Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/7569070083e6cd5b279bb5023da601aba3c06f3c.1597770847.git.christophe.leroy@csgroup.eu

powerpc/ptrace: Create ptrace_get_fpr() and ptrace_put_fpr()

2020-12-03T14:01:11Z

On the same model as ptrace_get_reg() and ptrace_put_reg(), create ptrace_get_fpr() and ptrace_put_fpr() to get/set the floating points registers. We move the boundary checkings in them. Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/24a1baedea7f7ae7b6bf27be98bab6d01b5ca2c1.1597770847.git.christophe.leroy@csgroup.eu

powerpc/ptrace: Consolidate reg index calculation

2020-12-03T14:01:11Z

Today we have: #ifdef CONFIG_PPC32 index = addr >> 2; if ((addr & 3) || child->thread.regs == NULL) #else index = addr >> 3; if ((addr & 7)) #endif sizeof(long) has value 4 for PPC32 and value 8 for PPC64. Dividing by 4 is equivalent to >> 2 and dividing by 8 is equivalent to >> 3. And 3 and 7 are respectively (sizeof(long) - 1). Use sizeof(long) to get rid of the #ifdef CONFIG_PPC32 and consolidate the calculation and checking. thread.regs have to be not NULL on both PPC32 and PPC64 so adding that test on PPC64 is harmless. Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/3cd1e284e93c60db981659585e18d1f6bb73ed2f.1597770847.git.christophe.leroy@csgroup.eu