From 726dcaa158b316f02f7dec2cf6dbf61c30a8bf22 Mon Sep 17 00:00:00 2001 From: Chen Gang Date: Mon, 20 May 2013 08:12:57 +0100 Subject: arm64: kernel: compiling issue, need 'EXPORT_SYMBOL(clear_page)' Need 'EXPORT_SYMBOL(clear_page)' if building with allmodconfig. The related errors: ERROR: "clear_page" [fs/ocfs2/dlm/ocfs2_dlm.ko] undefined! ERROR: "clear_page" [fs/ntfs/ntfs.ko] undefined! ERROR: "clear_page" [fs/gfs2/gfs2.ko] undefined! ERROR: "clear_page" [fs/fuse/fuse.ko] undefined! ERROR: "clear_page" [fs/ext3/ext3.ko] undefined! ERROR: "clear_page" [fs/ext2/ext2.ko] undefined! ERROR: "clear_page" [fs/exofs/libore.ko] undefined! ERROR: "clear_page" [fs/exofs/exofs.ko] undefined! ERROR: "clear_page" [drivers/block/brd.ko] undefined! Signed-off-by: Chen Gang Signed-off-by: Catalin Marinas --- arch/arm64/kernel/arm64ksyms.c | 1 + 1 file changed, 1 insertion(+) (limited to 'arch') diff --git a/arch/arm64/kernel/arm64ksyms.c b/arch/arm64/kernel/arm64ksyms.c index 7df1aad29b67..41b4f626d554 100644 --- a/arch/arm64/kernel/arm64ksyms.c +++ b/arch/arm64/kernel/arm64ksyms.c @@ -34,6 +34,7 @@ EXPORT_SYMBOL(__strnlen_user); EXPORT_SYMBOL(__strncpy_from_user); EXPORT_SYMBOL(copy_page); +EXPORT_SYMBOL(clear_page); EXPORT_SYMBOL(__copy_from_user); EXPORT_SYMBOL(__copy_to_user); -- cgit v1.2.3 From 953dbbed9ee310100bc841cdea8f992d192531c6 Mon Sep 17 00:00:00 2001 From: Catalin Marinas Date: Tue, 21 May 2013 12:16:56 +0100 Subject: arm64: Do not report user faults for handled signals Currently user faults (page, undefined instruction) are always reported even though the user may have a signal handler for them. This patch adds unhandled_signal() check together with printk_ratelimit() for these cases. Signed-off-by: Catalin Marinas --- arch/arm64/kernel/traps.c | 5 +++-- arch/arm64/mm/fault.c | 3 ++- 2 files changed, 5 insertions(+), 3 deletions(-) (limited to 'arch') diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c index 61d7dd29f756..f1ff9bad00f7 100644 --- a/arch/arm64/kernel/traps.c +++ b/arch/arm64/kernel/traps.c @@ -267,7 +267,8 @@ asmlinkage void __exception do_undefinstr(struct pt_regs *regs) return; #endif - if (show_unhandled_signals) { + if (show_unhandled_signals && unhandled_signal(current, SIGILL) && + printk_ratelimit()) { pr_info("%s[%d]: undefined instruction: pc=%p\n", current->comm, task_pid_nr(current), pc); dump_instr(KERN_INFO, regs); @@ -294,7 +295,7 @@ asmlinkage long do_ni_syscall(struct pt_regs *regs) } #endif - if (show_unhandled_signals) { + if (show_unhandled_signals && printk_ratelimit()) { pr_info("%s[%d]: syscall %d\n", current->comm, task_pid_nr(current), (int)regs->syscallno); dump_instr("", regs); diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c index 98af6e760cce..1426468b77f3 100644 --- a/arch/arm64/mm/fault.c +++ b/arch/arm64/mm/fault.c @@ -113,7 +113,8 @@ static void __do_user_fault(struct task_struct *tsk, unsigned long addr, { struct siginfo si; - if (show_unhandled_signals) { + if (show_unhandled_signals && unhandled_signal(tsk, sig) && + printk_ratelimit()) { pr_info("%s[%d]: unhandled %s (%d) at 0x%08lx, esr 0x%03x\n", tsk->comm, task_pid_nr(tsk), fault_name(esr), sig, addr, esr); -- cgit v1.2.3 From 381cc2b9705512ee7c7f1839cbdde374625a2a9f Mon Sep 17 00:00:00 2001 From: Mark Rutland Date: Fri, 24 May 2013 12:02:35 +0100 Subject: arm64: treat unhandled compat el0 traps as undef Currently, if a compat process reads or writes from/to a disabled cp15/cp14 register, the trap is not handled by the el0_sync_compat handler, and the kernel will head to bad_mode, where it will die(), and oops(). For 64 bit processes, disabled system register accesses are currently treated as unhandled instructions. This patch modifies entry.S to treat these unhandled traps as undefined instructions, sending a SIGILL to userspace. This gives processes a chance to handle this and stop using inaccessible registers, and prevents further issues in the kernel as a result of the die(). Reported-by: Johannes Jensen Signed-off-by: Mark Rutland Signed-off-by: Catalin Marinas --- arch/arm64/kernel/entry.S | 10 ++++++++++ 1 file changed, 10 insertions(+) (limited to 'arch') diff --git a/arch/arm64/kernel/entry.S b/arch/arm64/kernel/entry.S index c7e047049f2c..1d1314280a03 100644 --- a/arch/arm64/kernel/entry.S +++ b/arch/arm64/kernel/entry.S @@ -390,6 +390,16 @@ el0_sync_compat: b.eq el0_fpsimd_exc cmp x24, #ESR_EL1_EC_UNKNOWN // unknown exception in EL0 b.eq el0_undef + cmp x24, #ESR_EL1_EC_CP15_32 // CP15 MRC/MCR trap + b.eq el0_undef + cmp x24, #ESR_EL1_EC_CP15_64 // CP15 MRRC/MCRR trap + b.eq el0_undef + cmp x24, #ESR_EL1_EC_CP14_MR // CP14 MRC/MCR trap + b.eq el0_undef + cmp x24, #ESR_EL1_EC_CP14_LS // CP14 LDC/STC trap + b.eq el0_undef + cmp x24, #ESR_EL1_EC_CP14_64 // CP14 MRRC/MCRR trap + b.eq el0_undef cmp x24, #ESR_EL1_EC_BREAKPT_EL0 // debug exception in EL0 b.ge el0_dbg b el0_inv -- cgit v1.2.3 From 9955ac47f4ba1c95ecb6092aeaefb40a22e99268 Mon Sep 17 00:00:00 2001 From: Mark Rutland Date: Tue, 28 May 2013 15:54:15 +0100 Subject: arm64: don't kill the kernel on a bad esr from el0 Rather than completely killing the kernel if we receive an esr value we can't deal with in the el0 handlers, send the process a SIGILL and log the esr value in the hope that we can debug it. If we receive a bad esr from el1, we'll die() as before. Signed-off-by: Mark Rutland Signed-off-by: Catalin Marinas Cc: stable@vger.kernel.org --- arch/arm64/kernel/traps.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) (limited to 'arch') diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c index f1ff9bad00f7..f30852d28590 100644 --- a/arch/arm64/kernel/traps.c +++ b/arch/arm64/kernel/traps.c @@ -311,14 +311,20 @@ asmlinkage long do_ni_syscall(struct pt_regs *regs) */ asmlinkage void bad_mode(struct pt_regs *regs, int reason, unsigned int esr) { + siginfo_t info; + void __user *pc = (void __user *)instruction_pointer(regs); console_verbose(); pr_crit("Bad mode in %s handler detected, code 0x%08x\n", handler[reason], esr); + __show_regs(regs); + + info.si_signo = SIGILL; + info.si_errno = 0; + info.si_code = ILL_ILLOPC; + info.si_addr = pc; - die("Oops - bad mode", regs, 0); - local_irq_disable(); - panic("bad mode"); + arm64_notify_die("Oops - bad mode", regs, &info, 0); } void __pte_error(const char *file, int line, unsigned long val) -- cgit v1.2.3