user/sven/linux.git/arch, branch v4.9.284

s390/bpf: Fix optimizing out zero-extensions

2021-09-26T11:36:17Z

commit db7bee653859ef7179be933e7d1384644f795f26 upstream. Currently the JIT completely removes things like `reg32 += 0`, however, the BPF_ALU semantics requires the target register to be zero-extended in such cases. Fix by optimizing out only the arithmetic operation, but not the subsequent zero-extension. Reported-by: Johan Almbladh Fixes: 054623105728 ("s390/bpf: Add s390x eBPF JIT compiler backend") Reviewed-by: Heiko Carstens Signed-off-by: Ilya Leoshkevich Signed-off-by: Vasily Gorbik Signed-off-by: Greg Kroah-Hartman

s390/bpf: Fix 64-bit subtraction of the -0x80000000 constant

2021-09-22T09:43:10Z

commit 6e61dc9da0b7a0d91d57c2e20b5ea4fd2d4e7e53 upstream. The JIT uses agfi for subtracting constants, but -(-0x80000000) cannot be represented as a 32-bit signed binary integer. Fix by using algfi in this particular case. Reported-by: Johan Almbladh Fixes: 054623105728 ("s390/bpf: Add s390x eBPF JIT compiler backend") Reviewed-by: Heiko Carstens Signed-off-by: Ilya Leoshkevich Signed-off-by: Vasily Gorbik Signed-off-by: Greg Kroah-Hartman

ARC: export clear_user_page() for modules

2021-09-22T09:43:10Z

[ Upstream commit 6b5ff0405e4190f23780362ea324b250bc495683 ] 0day bot reports a build error: ERROR: modpost: "clear_user_page" [drivers/media/v4l2-core/videobuf-dma-sg.ko] undefined! so export it in arch/arc/ to fix the build error. In most ARCHes, clear_user_page() is a macro. OTOH, in a few ARCHes it is a function and needs to be exported. PowerPC exported it in 2004. It looks like nds32 and nios2 still need to have it exported. Fixes: 4102b53392d63 ("ARC: [mm] Aliasing VIPT dcache support 2/4") Signed-off-by: Randy Dunlap Reported-by: kernel test robot Cc: Guenter Roeck Cc: linux-snps-arc@lists.infradead.org Signed-off-by: Vineet Gupta Signed-off-by: Sasha Levin

x86/mm: Fix kern_addr_valid() to cope with existing but not present entries

2021-09-22T09:43:09Z

commit 34b1999da935a33be6239226bfa6cd4f704c5c88 upstream. Jiri Olsa reported a fault when running: # cat /proc/kallsyms | grep ksys_read ffffffff8136d580 T ksys_read # objdump -d --start-address=0xffffffff8136d580 --stop-address=0xffffffff8136d590 /proc/kcore /proc/kcore: file format elf64-x86-64 Segmentation fault general protection fault, probably for non-canonical address 0xf887ffcbff000: 0000 [#1] SMP PTI CPU: 12 PID: 1079 Comm: objdump Not tainted 5.14.0-rc5qemu+ #508 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-4.fc34 04/01/2014 RIP: 0010:kern_addr_valid Call Trace: read_kcore ? rcu_read_lock_sched_held ? rcu_read_lock_sched_held ? rcu_read_lock_sched_held ? trace_hardirqs_on ? rcu_read_lock_sched_held ? lock_acquire ? lock_acquire ? rcu_read_lock_sched_held ? lock_acquire ? rcu_read_lock_sched_held ? rcu_read_lock_sched_held ? rcu_read_lock_sched_held ? lock_release ? _raw_spin_unlock ? __handle_mm_fault ? rcu_read_lock_sched_held ? lock_acquire ? rcu_read_lock_sched_held ? lock_release proc_reg_read ? vfs_read vfs_read ksys_read do_syscall_64 entry_SYSCALL_64_after_hwframe The fault happens because kern_addr_valid() dereferences existent but not present PMD in the high kernel mappings. Such PMDs are created when free_kernel_image_pages() frees regions larger than 2Mb. In this case, a part of the freed memory is mapped with PMDs and the set_memory_np_noalias() -> ... -> __change_page_attr() sequence will mark the PMD as not present rather than wipe it completely. Have kern_addr_valid() check whether higher level page table entries are present before trying to dereference them to fix this issue and to avoid similar issues in the future. Stable backporting note: ------------------------ Note that the stable marking is for all active stable branches because there could be cases where pagetable entries exist but are not valid - see 9a14aefc1d28 ("x86: cpa, fix lookup_address"), for example. So make sure to be on the safe side here and use pXY_present() accessors rather than pXY_none() which could #GP when accessing pages in the direct map. Also see: c40a56a7818c ("x86/mm/init: Remove freed kernel image areas from alias mapping") for more info. Reported-by: Jiri Olsa Signed-off-by: Mike Rapoport Signed-off-by: Borislav Petkov Reviewed-by: David Hildenbrand Acked-by: Dave Hansen Tested-by: Jiri Olsa Cc: # 4.4+ Link: https://lkml.kernel.org/r/20210819132717.19358-1-rppt@kernel.org Signed-off-by: Greg Kroah-Hartman

xen: reset legacy rtc flag for PV domU

2021-09-22T09:43:08Z

commit f68aa100d815b5b4467fd1c3abbe3b99d65fd028 upstream. A Xen PV guest doesn't have a legacy RTC device, so reset the legacy RTC flag. Otherwise the following WARN splat will occur at boot: [ 1.333404] WARNING: CPU: 1 PID: 1 at /home/gross/linux/head/drivers/rtc/rtc-mc146818-lib.c:25 mc146818_get_time+0x1be/0x210 [ 1.333404] Modules linked in: [ 1.333404] CPU: 1 PID: 1 Comm: swapper/0 Tainted: G W 5.14.0-rc7-default+ #282 [ 1.333404] RIP: e030:mc146818_get_time+0x1be/0x210 [ 1.333404] Code: c0 64 01 c5 83 fd 45 89 6b 14 7f 06 83 c5 64 89 6b 14 41 83 ec 01 b8 02 00 00 00 44 89 63 10 5b 5d 41 5c 41 5d 41 5e 41 5f c3 <0f> 0b 48 c7 c7 30 0e ef 82 4c 89 e6 e8 71 2a 24 00 48 c7 c0 ff ff [ 1.333404] RSP: e02b:ffffc90040093df8 EFLAGS: 00010002 [ 1.333404] RAX: 00000000000000ff RBX: ffffc90040093e34 RCX: 0000000000000000 [ 1.333404] RDX: 0000000000000001 RSI: 0000000000000000 RDI: 000000000000000d [ 1.333404] RBP: ffffffff82ef0e30 R08: ffff888005013e60 R09: 0000000000000000 [ 1.333404] R10: ffffffff82373e9b R11: 0000000000033080 R12: 0000000000000200 [ 1.333404] R13: 0000000000000000 R14: 0000000000000002 R15: ffffffff82cdc6d4 [ 1.333404] FS: 0000000000000000(0000) GS:ffff88807d440000(0000) knlGS:0000000000000000 [ 1.333404] CS: 10000e030 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 1.333404] CR2: 0000000000000000 CR3: 000000000260a000 CR4: 0000000000050660 [ 1.333404] Call Trace: [ 1.333404] ? wakeup_sources_sysfs_init+0x30/0x30 [ 1.333404] ? rdinit_setup+0x2b/0x2b [ 1.333404] early_resume_init+0x23/0xa4 [ 1.333404] ? cn_proc_init+0x36/0x36 [ 1.333404] do_one_initcall+0x3e/0x200 [ 1.333404] kernel_init_freeable+0x232/0x28e [ 1.333404] ? rest_init+0xd0/0xd0 [ 1.333404] kernel_init+0x16/0x120 [ 1.333404] ret_from_fork+0x1f/0x30 Cc: Fixes: 8d152e7a5c7537 ("x86/rtc: Replace paravirt rtc check with platform legacy quirk") Signed-off-by: Juergen Gross Reviewed-by: Boris Ostrovsky Link: https://lore.kernel.org/r/20210903084937.19392-3-jgross@suse.com Signed-off-by: Juergen Gross Signed-off-by: Greg Kroah-Hartman

parisc: fix crash with signals and alloca

2021-09-22T09:43:08Z

commit 030f653078316a9cc9ca6bd1b0234dcf858be35d upstream. I was debugging some crashes on parisc and I found out that there is a crash possibility if a function using alloca is interrupted by a signal. The reason for the crash is that the gcc alloca implementation leaves garbage in the upper 32 bits of the sp register. This normally doesn't matter (the upper bits are ignored because the PSW W-bit is clear), however the signal delivery routine in the kernel uses full 64 bits of sp and it fails with -EFAULT if the upper 32 bits are not zero. I created this program that demonstrates the problem: #include #include #include #include static __attribute__((noinline,noclone)) void aa(int *size) { void * volatile p = alloca(-*size); while (1) ; } static void handler(int sig) { write(1, "signal delivered\n", 17); _exit(0); } int main(void) { int size = -0x100; signal(SIGALRM, handler); alarm(1); aa(&size); } If you compile it with optimizations, it will crash. The "aa" function has this disassembly: 000106a0 : 106a0: 08 03 02 41 copy r3,r1 106a4: 08 1e 02 43 copy sp,r3 106a8: 6f c1 00 80 stw,ma r1,40(sp) 106ac: 37 dc 3f c1 ldo -20(sp),ret0 106b0: 0c 7c 12 90 stw ret0,8(r3) 106b4: 0f 40 10 9c ldw 0(r26),ret0 ; ret0 = 0x00000000FFFFFF00 106b8: 97 9c 00 7e subi 3f,ret0,ret0 ; ret0 = 0xFFFFFFFF0000013F 106bc: d7 80 1c 1a depwi 0,31,6,ret0 ; ret0 = 0xFFFFFFFF00000100 106c0: 0b 9e 0a 1e add,l sp,ret0,sp ; sp = 0xFFFFFFFFxxxxxxxx 106c4: e8 1f 1f f7 b,l,n 106c4 ,r0 This patch fixes the bug by truncating the "usp" variable to 32 bits. Signed-off-by: Mikulas Patocka Cc: stable@vger.kernel.org Signed-off-by: Helge Deller Signed-off-by: Greg Kroah-Hartman

ARM: tegra: tamonten: Fix UART pad setting

2021-09-22T09:43:07Z

[ Upstream commit 2270ad2f4e123336af685ecedd1618701cb4ca1e ] This patch fixes the tristate and pullup configuration for UART 1 to 3 on the Tamonten SOM. Signed-off-by: Andreas Obergschwandtner Signed-off-by: Thierry Reding Signed-off-by: Sasha Levin

xtensa: ISS: don't panic in rs_init

2021-09-22T09:43:06Z

[ Upstream commit 23411c720052ad860b3e579ee4873511e367130a ] While alloc_tty_driver failure in rs_init would mean we have much bigger problem, there is no reason to panic when tty_register_driver fails there. It can fail for various reasons. So handle the failure gracefully. Actually handle them both while at it. This will make at least the console functional as it was enabled earlier by console_initcall in iss_console_init. Instead of shooting down the whole system. We move tty_port_init() after alloc_tty_driver(), so that we don't need to destroy the port in case the latter function fails. Cc: Chris Zankel Cc: Max Filippov Cc: linux-xtensa@linux-xtensa.org Acked-by: Max Filippov Signed-off-by: Jiri Slaby Link: https://lore.kernel.org/r/20210723074317.32690-2-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin

s390/jump_label: print real address in a case of a jump label bug

2021-09-22T09:43:06Z

[ Upstream commit 5492886c14744d239e87f1b0b774b5a341e755cc ] In case of a jump label print the real address of the piece of code where a mismatch was detected. This is right before the system panics, so there is nothing revealed. Signed-off-by: Heiko Carstens Signed-off-by: Sasha Levin

MIPS: Malta: fix alignment of the devicetree buffer

2021-09-22T09:43:04Z

[ Upstream commit bea6a94a279bcbe6b2cde348782b28baf12255a5 ] Starting with following patch MIPS Malta is not able to boot: | commit 79edff12060fe7772af08607eff50c0e2486c5ba | Author: Rob Herring | scripts/dtc: Update to upstream version v1.6.0-51-g183df9e9c2b9 The reason is the alignment test added to the fdt_ro_probe_(). To fix this issue, we need to make sure that fdt_buf is aligned. Since the dtc patch was designed to uncover potential issue, I handle initial MIPS Malta patch as initial bug. Fixes: e81a8c7dabac ("MIPS: Malta: Setup RAM regions via DT") Signed-off-by: Oleksij Rempel Signed-off-by: Thomas Bogendoerfer Signed-off-by: Sasha Levin