From ac8b4d3ed1a1e995ce821064ce54a22c24d88294 Mon Sep 17 00:00:00 2001 From: Johan Hovold Date: Mon, 17 Jul 2017 09:28:20 +0100 Subject: ARM: 8688/1: pm: add missing types include Add missing types.h include to make the suspend header self-contained and avoid compilation breakage due to include-directive ordering. Acked-by: Pavel Machek Signed-off-by: Johan Hovold Signed-off-by: Russell King --- arch/arm/include/asm/suspend.h | 2 ++ 1 file changed, 2 insertions(+) diff --git a/arch/arm/include/asm/suspend.h b/arch/arm/include/asm/suspend.h index 6c7182f32cef..a61905c86732 100644 --- a/arch/arm/include/asm/suspend.h +++ b/arch/arm/include/asm/suspend.h @@ -1,6 +1,8 @@ #ifndef __ASM_ARM_SUSPEND_H #define __ASM_ARM_SUSPEND_H +#include + struct sleep_save_sp { u32 *save_ptr_stash; u32 save_ptr_stash_phys; -- cgit v1.2.3 From fed3c15531a225d95ec9b0aba4ff01c38de7a1b9 Mon Sep 17 00:00:00 2001 From: Johan Hovold Date: Mon, 17 Jul 2017 09:28:19 +0100 Subject: ARM: 8689/1: scu: add missing errno include Add missing errno include to make the header self-contained and avoid compilation breakage when compiling shared code without CONFIG_HAVE_ARM_SCU. Signed-off-by: Johan Hovold Signed-off-by: Russell King --- arch/arm/include/asm/smp_scu.h | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/arm/include/asm/smp_scu.h b/arch/arm/include/asm/smp_scu.h index bfe163c40024..5983f6bc62d5 100644 --- a/arch/arm/include/asm/smp_scu.h +++ b/arch/arm/include/asm/smp_scu.h @@ -7,6 +7,7 @@ #ifndef __ASSEMBLER__ +#include #include static inline bool scu_a9_has_base(void) -- cgit v1.2.3 From 309ee04257d473ce87f2c7e99f6d69e933d307e3 Mon Sep 17 00:00:00 2001 From: Russell King Date: Fri, 24 Mar 2017 16:15:45 +0000 Subject: ARM: use aliases for registers in entry-common Use aliases for the saved (and preserved) PSR and PC values so that we can control which registers are used. Signed-off-by: Russell King --- arch/arm/kernel/entry-common.S | 24 ++++++++++++++---------- 1 file changed, 14 insertions(+), 10 deletions(-) diff --git a/arch/arm/kernel/entry-common.S b/arch/arm/kernel/entry-common.S index eb5cd77bf1d8..9abe47a206d9 100644 --- a/arch/arm/kernel/entry-common.S +++ b/arch/arm/kernel/entry-common.S @@ -27,6 +27,8 @@ #include "entry-header.S" +saved_psr .req r8 +saved_pc .req lr .align 5 #if !(IS_ENABLED(CONFIG_TRACE_IRQFLAGS) || IS_ENABLED(CONFIG_CONTEXT_TRACKING)) @@ -141,9 +143,9 @@ ENTRY(vector_swi) ARM( stmdb r8, {sp, lr}^ ) @ Calling sp, lr THUMB( mov r8, sp ) THUMB( store_user_sp_lr r8, r10, S_SP ) @ calling sp, lr - mrs r8, spsr @ called from non-FIQ mode, so ok. - str lr, [sp, #S_PC] @ Save calling PC - str r8, [sp, #S_PSR] @ Save CPSR + mrs saved_psr, spsr @ called from non-FIQ mode, so ok. + str saved_pc, [sp, #S_PC] @ Save calling PC + str saved_psr, [sp, #S_PSR] @ Save CPSR str r0, [sp, #S_OLD_R0] @ Save OLD_R0 #endif zero_fp @@ -163,11 +165,11 @@ ENTRY(vector_swi) * value to determine if it is an EABI or an old ABI call. */ #ifdef CONFIG_ARM_THUMB - tst r8, #PSR_T_BIT + tst saved_psr, #PSR_T_BIT movne r10, #0 @ no thumb OABI emulation - USER( ldreq r10, [lr, #-4] ) @ get SWI instruction + USER( ldreq r10, [saved_pc, #-4] ) @ get SWI instruction #else - USER( ldr r10, [lr, #-4] ) @ get SWI instruction + USER( ldr r10, [saved_pc, #-4] ) @ get SWI instruction #endif ARM_BE8(rev r10, r10) @ little endian instruction @@ -178,15 +180,17 @@ ENTRY(vector_swi) */ #elif defined(CONFIG_ARM_THUMB) /* Legacy ABI only, possibly thumb mode. */ - tst r8, #PSR_T_BIT @ this is SPSR from save_user_regs + tst saved_psr, #PSR_T_BIT @ this is SPSR from save_user_regs addne scno, r7, #__NR_SYSCALL_BASE @ put OS number in - USER( ldreq scno, [lr, #-4] ) + USER( ldreq scno, [saved_pc, #-4] ) #else /* Legacy ABI only. */ - USER( ldr scno, [lr, #-4] ) @ get SWI instruction + USER( ldr scno, [saved_pc, #-4] ) @ get SWI instruction #endif + /* saved_psr and saved_pc are now dead */ + uaccess_disable tbl adr tbl, sys_call_table @ load syscall table pointer @@ -234,7 +238,7 @@ local_restart: * current task. */ 9001: - sub lr, lr, #4 + sub lr, saved_pc, #4 str lr, [sp, #S_PC] b ret_fast_syscall #endif -- cgit v1.2.3 From da594e3fff398a164c77dd728d9fbfc6880881e6 Mon Sep 17 00:00:00 2001 From: Russell King Date: Fri, 24 Mar 2017 16:19:12 +0000 Subject: ARM: obtain thread info structure later Obtain the thread info structure later in the syscall processing, so that we free up a register for earlier code. Signed-off-by: Russell King --- arch/arm/kernel/entry-common.S | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/arch/arm/kernel/entry-common.S b/arch/arm/kernel/entry-common.S index 9abe47a206d9..374c28723547 100644 --- a/arch/arm/kernel/entry-common.S +++ b/arch/arm/kernel/entry-common.S @@ -152,7 +152,6 @@ ENTRY(vector_swi) alignment_trap r10, ip, __cr_alignment enable_irq ct_user_exit - get_thread_info tsk /* * Get the system call number. @@ -209,6 +208,7 @@ ENTRY(vector_swi) bic scno, scno, #0xff000000 @ mask off SWI op-code eor scno, scno, #__NR_SYSCALL_BASE @ check OS number #endif + get_thread_info tsk local_restart: ldr r10, [tsk, #TI_FLAGS] @ check for syscall tracing @@ -240,6 +240,7 @@ local_restart: 9001: sub lr, saved_pc, #4 str lr, [sp, #S_PC] + get_thread_info tsk b ret_fast_syscall #endif ENDPROC(vector_swi) -- cgit v1.2.3 From fcea45236d3ffcd317296d75612eb163bf734407 Mon Sep 17 00:00:00 2001 From: Russell King Date: Fri, 24 Mar 2017 16:22:10 +0000 Subject: ARM: move PC value into r9 Move the saved PC value into r9, thereby moving it into a caller-saved register for functions that we may call during the entry to a syscall. Signed-off-by: Russell King --- arch/arm/kernel/entry-common.S | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/arch/arm/kernel/entry-common.S b/arch/arm/kernel/entry-common.S index 374c28723547..1b3fc79d0e8b 100644 --- a/arch/arm/kernel/entry-common.S +++ b/arch/arm/kernel/entry-common.S @@ -28,7 +28,13 @@ #include "entry-header.S" saved_psr .req r8 +#if defined(CONFIG_TRACE_IRQFLAGS) || defined(CONFIG_CONTEXT_TRACKING) +saved_pc .req r9 +#define TRACE(x...) x +#else saved_pc .req lr +#define TRACE(x...) +#endif .align 5 #if !(IS_ENABLED(CONFIG_TRACE_IRQFLAGS) || IS_ENABLED(CONFIG_CONTEXT_TRACKING)) @@ -144,6 +150,7 @@ ENTRY(vector_swi) THUMB( mov r8, sp ) THUMB( store_user_sp_lr r8, r10, S_SP ) @ calling sp, lr mrs saved_psr, spsr @ called from non-FIQ mode, so ok. + TRACE( mov saved_pc, lr ) str saved_pc, [sp, #S_PC] @ Save calling PC str saved_psr, [sp, #S_PSR] @ Save CPSR str r0, [sp, #S_OLD_R0] @ Save OLD_R0 -- cgit v1.2.3 From dca778c5bbf3f1cfcf7f6ef6cadf5a7e5c5d972f Mon Sep 17 00:00:00 2001 From: Russell King Date: Fri, 24 Mar 2017 16:23:25 +0000 Subject: ARM: avoid saving and restoring registers unnecessarily Avoid repeatedly saving and restoring registers around the calls to trace_hardirqs_on() and context_tracking_user_exit(). With the previous changes, we no longer need to preserve "lr" across these calls, and if we re-load r0-r3 later, we can avoid preserving these regsiters too. Signed-off-by: Russell King --- arch/arm/kernel/entry-common.S | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/arch/arm/kernel/entry-common.S b/arch/arm/kernel/entry-common.S index 1b3fc79d0e8b..0b60adf4a5d9 100644 --- a/arch/arm/kernel/entry-common.S +++ b/arch/arm/kernel/entry-common.S @@ -157,8 +157,9 @@ ENTRY(vector_swi) #endif zero_fp alignment_trap r10, ip, __cr_alignment - enable_irq - ct_user_exit + asm_trace_hardirqs_on save=0 + enable_irq_notrace + ct_user_exit save=0 /* * Get the system call number. @@ -216,6 +217,11 @@ ENTRY(vector_swi) eor scno, scno, #__NR_SYSCALL_BASE @ check OS number #endif get_thread_info tsk + /* + * Reload the registers that may have been corrupted on entry to + * the syscall assembly (by tracing or context tracking.) + */ + TRACE( ldmia sp, {r0 - r3} ) local_restart: ldr r10, [tsk, #TI_FLAGS] @ check for syscall tracing -- cgit v1.2.3 From 494609701e06a0040c0f4042c80fac4e8b5f0ab8 Mon Sep 17 00:00:00 2001 From: Russell King Date: Wed, 14 Jun 2017 10:25:18 +0100 Subject: ARM: always enable AEABI for ARMv6+ Always enable AEABI for ARMv6+, as these use the double-word exclusives which must be passed an even register to avoid errors such as: /tmp/ccG2rCwe.s:905: Error: even register required -- `ldrexd r5,r6,[r7]' /tmp/ccG2rCwe.s:909: Error: even register required -- `strexd sl,r3,r4,[r7]' Signed-off-by: Russell King --- arch/arm/Kconfig | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index a208bfe367b5..1cd85410a89a 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -1531,7 +1531,6 @@ config THUMB2_KERNEL bool "Compile the kernel in Thumb-2 mode" if !CPU_THUMBONLY depends on (CPU_V7 || CPU_V7M) && !CPU_V6 && !CPU_V6K default y if CPU_THUMBONLY - select AEABI select ARM_ASM_UNIFIED select ARM_UNWIND help @@ -1594,7 +1593,8 @@ config ARM_PATCH_IDIV code to do integer division. config AEABI - bool "Use the ARM EABI to compile the kernel" + bool "Use the ARM EABI to compile the kernel" if !CPU_V7 && !CPU_V7M && !CPU_V6 && !CPU_V6K + default CPU_V7 || CPU_V7M || CPU_V6 || CPU_V6K help This option allows for the kernel to be compiled using the latest ARM ABI (aka EABI). This is only useful if you are using a user -- cgit v1.2.3 From 1abd35023763c099bf4ee7558faa261d5c9d5025 Mon Sep 17 00:00:00 2001 From: Russell King Date: Wed, 26 Jul 2017 12:49:31 +0100 Subject: ARM: align .data section Robert Jarzmik reports that his PXA25x system fails to boot with 4.12, failing at __flush_whole_cache in arch/arm/mm/proc-xscale.S:215: 0xc0019e20 <+0>: ldr r1, [pc, #788] 0xc0019e24 <+4>: ldr r0, [r1] <== here with r1 containing 0xc06f82cd, which is the address of "clean_addr". Examination of the System.map shows: c06f22c8 D user_pmd_table c06f22cc d __warned.19178 c06f22cd d clean_addr indicating that a .data.unlikely section has appeared just before the .data section from proc-xscale.S. According to objdump -h, it appears that our assembly files default their .data alignment to 2**0, which is bad news if the preceding .data section size is not power-of-2 aligned at link time. Add the appropriate .align directives to all assembly files in arch/arm that are missing them where we require an appropriate alignment. Reported-by: Robert Jarzmik Tested-by: Robert Jarzmik Signed-off-by: Russell King --- arch/arm/include/debug/omap2plus.S | 1 + arch/arm/kernel/entry-armv.S | 2 ++ arch/arm/kernel/head.S | 2 ++ arch/arm/kernel/hyp-stub.S | 1 + arch/arm/kernel/iwmmxt.S | 1 + arch/arm/kernel/sleep.S | 1 + arch/arm/mach-exynos/sleep.S | 1 + arch/arm/mach-omap2/sleep34xx.S | 2 ++ arch/arm/mach-omap2/sleep44xx.S | 1 + arch/arm/mach-pxa/mioa701_bootresume.S | 2 ++ arch/arm/mach-rockchip/sleep.S | 2 +- arch/arm/mm/cache-v4wb.S | 1 + arch/arm/mm/proc-xscale.S | 1 + 13 files changed, 17 insertions(+), 1 deletion(-) diff --git a/arch/arm/include/debug/omap2plus.S b/arch/arm/include/debug/omap2plus.S index 6d867aef18eb..78e7e58a58f6 100644 --- a/arch/arm/include/debug/omap2plus.S +++ b/arch/arm/include/debug/omap2plus.S @@ -59,6 +59,7 @@ #define UART_OFFSET(addr) ((addr) & 0x00ffffff) .pushsection .data + .align 2 omap_uart_phys: .word 0 omap_uart_virt: .word 0 omap_uart_lsr: .word 0 diff --git a/arch/arm/kernel/entry-armv.S b/arch/arm/kernel/entry-armv.S index 9f157e7c51e7..4c0b9e569a9e 100644 --- a/arch/arm/kernel/entry-armv.S +++ b/arch/arm/kernel/entry-armv.S @@ -721,6 +721,7 @@ do_fpe: */ .pushsection .data + .align 2 ENTRY(fp_enter) .word no_fp .popsection @@ -1221,6 +1222,7 @@ vector_addrexcptn: W(b) vector_fiq .data + .align 2 .globl cr_alignment cr_alignment: diff --git a/arch/arm/kernel/head.S b/arch/arm/kernel/head.S index 04286fd9e09c..6b1148cafffd 100644 --- a/arch/arm/kernel/head.S +++ b/arch/arm/kernel/head.S @@ -556,6 +556,7 @@ ENDPROC(__fixup_smp) .word __smpalt_end .pushsection .data + .align 2 .globl smp_on_up smp_on_up: ALT_SMP(.long 1) @@ -716,6 +717,7 @@ ENTRY(fixup_pv_table) ENDPROC(fixup_pv_table) .data + .align 2 .globl __pv_phys_pfn_offset .type __pv_phys_pfn_offset, %object __pv_phys_pfn_offset: diff --git a/arch/arm/kernel/hyp-stub.S b/arch/arm/kernel/hyp-stub.S index ec7e7377d423..60146e32619a 100644 --- a/arch/arm/kernel/hyp-stub.S +++ b/arch/arm/kernel/hyp-stub.S @@ -31,6 +31,7 @@ * zeroing of .bss would clobber it. */ .data + .align 2 ENTRY(__boot_cpu_mode) .long 0 .text diff --git a/arch/arm/kernel/iwmmxt.S b/arch/arm/kernel/iwmmxt.S index 49fadbda8c63..81cd4d43b3ec 100644 --- a/arch/arm/kernel/iwmmxt.S +++ b/arch/arm/kernel/iwmmxt.S @@ -367,6 +367,7 @@ ENTRY(iwmmxt_task_release) ENDPROC(iwmmxt_task_release) .data + .align 2 concan_owner: .word 0 diff --git a/arch/arm/kernel/sleep.S b/arch/arm/kernel/sleep.S index 0f6c1000582c..9f08d214d05a 100644 --- a/arch/arm/kernel/sleep.S +++ b/arch/arm/kernel/sleep.S @@ -171,6 +171,7 @@ mpidr_hash_ptr: .long mpidr_hash - . @ mpidr_hash struct offset .data + .align 2 .type sleep_save_sp, #object ENTRY(sleep_save_sp) .space SLEEP_SAVE_SP_SZ @ struct sleep_save_sp diff --git a/arch/arm/mach-exynos/sleep.S b/arch/arm/mach-exynos/sleep.S index cf950790fbdc..4292cae43f3c 100644 --- a/arch/arm/mach-exynos/sleep.S +++ b/arch/arm/mach-exynos/sleep.S @@ -124,6 +124,7 @@ _cp15_save_diag: #endif /* CONFIG_CACHE_L2X0 */ .data + .align 2 .globl cp15_save_diag cp15_save_diag: .long 0 @ cp15 diagnostic diff --git a/arch/arm/mach-omap2/sleep34xx.S b/arch/arm/mach-omap2/sleep34xx.S index 1b9f0520dea9..fa5fd24f524c 100644 --- a/arch/arm/mach-omap2/sleep34xx.S +++ b/arch/arm/mach-omap2/sleep34xx.S @@ -530,10 +530,12 @@ l2dis_3630_offset: .long l2dis_3630 - . .data + .align 2 l2dis_3630: .word 0 .data + .align 2 l2_inv_api_params: .word 0x1, 0x00 diff --git a/arch/arm/mach-omap2/sleep44xx.S b/arch/arm/mach-omap2/sleep44xx.S index c7a3b4aab4b5..56dfa2d5d0a8 100644 --- a/arch/arm/mach-omap2/sleep44xx.S +++ b/arch/arm/mach-omap2/sleep44xx.S @@ -385,6 +385,7 @@ ppa_zero_params_offset: ENDPROC(omap_do_wfi) .data + .align 2 ppa_zero_params: .word 0 diff --git a/arch/arm/mach-pxa/mioa701_bootresume.S b/arch/arm/mach-pxa/mioa701_bootresume.S index 81591491ab94..42d93f40a59f 100644 --- a/arch/arm/mach-pxa/mioa701_bootresume.S +++ b/arch/arm/mach-pxa/mioa701_bootresume.S @@ -16,6 +16,7 @@ * insist on it to be truly read-only. */ .data + .align 2 ENTRY(mioa701_bootstrap) 0: b 1f @@ -34,4 +35,5 @@ ENTRY(mioa701_jumpaddr) ENTRY(mioa701_bootstrap_lg) .data + .align 2 .word 2b-0b diff --git a/arch/arm/mach-rockchip/sleep.S b/arch/arm/mach-rockchip/sleep.S index 2eec9a341f05..9927f06f52fe 100644 --- a/arch/arm/mach-rockchip/sleep.S +++ b/arch/arm/mach-rockchip/sleep.S @@ -23,7 +23,7 @@ * ddr to sram for system resumeing. * so it is ".data section". */ -.align + .align 2 ENTRY(rockchip_slp_cpu_resume) setmode PSR_I_BIT | PSR_F_BIT | SVC_MODE, r1 @ set svc, irqs off diff --git a/arch/arm/mm/cache-v4wb.S b/arch/arm/mm/cache-v4wb.S index 2522f8c8fbb1..a5084ec70c6e 100644 --- a/arch/arm/mm/cache-v4wb.S +++ b/arch/arm/mm/cache-v4wb.S @@ -47,6 +47,7 @@ #define CACHE_DLIMIT (CACHE_DSIZE * 4) .data + .align 2 flush_base: .long FLUSH_BASE .text diff --git a/arch/arm/mm/proc-xscale.S b/arch/arm/mm/proc-xscale.S index b6bbfdb6dfdc..3d75b7972fd1 100644 --- a/arch/arm/mm/proc-xscale.S +++ b/arch/arm/mm/proc-xscale.S @@ -104,6 +104,7 @@ .endm .data + .align 2 clean_addr: .word CLEAN_ADDR .text -- cgit v1.2.3 From f26fee5f111d7221b5b0724a1a54a066dc8cf410 Mon Sep 17 00:00:00 2001 From: Hoeun Ryu Date: Mon, 7 Aug 2017 06:49:19 +0100 Subject: ARM: 8690/1: lpae: build TTB control register value from scratch in v7_ttb_setup Reading TTBCR in early boot stage might return the value of the previous kernel's configuration, especially in case of kexec. For example, if normal kernel (first kernel) had run on a configuration of PHYS_OFFSET <= PAGE_OFFSET and crash kernel (second kernel) is running on a configuration PHYS_OFFSET > PAGE_OFFSET, which can happen because it depends on the reserved area for crash kernel, reading TTBCR and using the value to OR other bit fields might be risky because it doesn't have a reset value for TTBCR. Suggested-by: Robin Murphy Signed-off-by: Hoeun Ryu Signed-off-by: Russell King --- arch/arm/mm/proc-v7-3level.S | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/arch/arm/mm/proc-v7-3level.S b/arch/arm/mm/proc-v7-3level.S index 5e5720e8bc5f..7d16bbc4102b 100644 --- a/arch/arm/mm/proc-v7-3level.S +++ b/arch/arm/mm/proc-v7-3level.S @@ -129,8 +129,7 @@ ENDPROC(cpu_v7_set_pte_ext) .macro v7_ttb_setup, zero, ttbr0l, ttbr0h, ttbr1, tmp ldr \tmp, =swapper_pg_dir @ swapper_pg_dir virtual address cmp \ttbr1, \tmp, lsr #12 @ PHYS_OFFSET > PAGE_OFFSET? - mrc p15, 0, \tmp, c2, c0, 2 @ TTB control egister - orr \tmp, \tmp, #TTB_EAE + mov \tmp, #TTB_EAE @ for TTB control egister ALT_SMP(orr \tmp, \tmp, #TTB_FLAGS_SMP) ALT_UP(orr \tmp, \tmp, #TTB_FLAGS_UP) ALT_SMP(orr \tmp, \tmp, #TTB_FLAGS_SMP << 16) -- cgit v1.2.3 From 746a272e44141af24a02f6c9b0f65f4c4598ed42 Mon Sep 17 00:00:00 2001 From: Mark Rutland Date: Tue, 22 Aug 2017 11:36:17 +0100 Subject: ARM: 8692/1: mm: abort uaccess retries upon fatal signal When there's a fatal signal pending, arm's do_page_fault() implementation returns 0. The intent is that we'll return to the faulting userspace instruction, delivering the signal on the way. However, if we take a fatal signal during fixing up a uaccess, this results in a return to the faulting kernel instruction, which will be instantly retried, resulting in the same fault being taken forever. As the task never reaches userspace, the signal is not delivered, and the task is left unkillable. While the task is stuck in this state, it can inhibit the forward progress of the system. To avoid this, we must ensure that when a fatal signal is pending, we apply any necessary fixup for a faulting kernel instruction. Thus we will return to an error path, and it is up to that code to make forward progress towards delivering the fatal signal. Signed-off-by: Mark Rutland Reviewed-by: Steve Capper Cc: stable@vger.kernel.org Signed-off-by: Russell King --- arch/arm/mm/fault.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/arch/arm/mm/fault.c b/arch/arm/mm/fault.c index ff8b0aa2dfde..42f585379e19 100644 --- a/arch/arm/mm/fault.c +++ b/arch/arm/mm/fault.c @@ -315,8 +315,11 @@ retry: * signal first. We do not need to release the mmap_sem because * it would already be released in __lock_page_or_retry in * mm/filemap.c. */ - if ((fault & VM_FAULT_RETRY) && fatal_signal_pending(current)) + if ((fault & VM_FAULT_RETRY) && fatal_signal_pending(current)) { + if (!user_mode(regs)) + goto no_context; return 0; + } /* * Major/minor page fault accounting is only done on the -- cgit v1.2.3 From 9a3dc3186fc3795e076a4122da9e0258651a9631 Mon Sep 17 00:00:00 2001 From: Dustin Brown Date: Mon, 7 Aug 2017 19:44:01 +0100 Subject: ARM: 8691/1: Export save_stack_trace_tsk() The kernel watchdog is a great debugging tool for finding tasks that consume a disproportionate amount of CPU time in contiguous chunks. One can imagine building a similar watchdog for arbitrary driver threads using save_stack_trace_tsk() and print_stack_trace(). However, this is not viable for dynamically loaded driver modules on ARM platforms because save_stack_trace_tsk() is not exported for those architectures. Export save_stack_trace_tsk() for the ARM architecture to align with x86 and support various debugging use cases such as arbitrary driver thread watchdog timers. Signed-off-by: Dustin Brown Signed-off-by: Russell King --- arch/arm/kernel/stacktrace.c | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/arm/kernel/stacktrace.c b/arch/arm/kernel/stacktrace.c index 3a2fa203637a..65228bf4c6df 100644 --- a/arch/arm/kernel/stacktrace.c +++ b/arch/arm/kernel/stacktrace.c @@ -171,6 +171,7 @@ void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace) { __save_stack_trace(tsk, trace, 1); } +EXPORT_SYMBOL(save_stack_trace_tsk); void save_stack_trace(struct stack_trace *trace) { -- cgit v1.2.3