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| author | Russell King <rmk+kernel@arm.linux.org.uk> | 2013-02-25 16:10:42 +0000 |
|---|---|---|
| committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2013-02-25 16:10:42 +0000 |
| commit | b255188f90e2bade1bd11a986dd1ca4861869f4d (patch) | |
| tree | 39df34896ae3bdac7ae41cb17078a1caaa5bf1ad | |
| parent | 5e4ba617c1b584b2e376f31a63bd4e734109318a (diff) | |
| download | linux-stable-b255188f90e2bade1bd11a986dd1ca4861869f4d.tar.gz linux-stable-b255188f90e2bade1bd11a986dd1ca4861869f4d.tar.bz2 linux-stable-b255188f90e2bade1bd11a986dd1ca4861869f4d.zip | |
ARM: fix scheduling while atomic warning in alignment handling code
Paolo Pisati reports that IPv6 triggers this warning:
BUG: scheduling while atomic: swapper/0/0/0x40000100
Modules linked in:
[<c001b1c4>] (unwind_backtrace+0x0/0xf0) from [<c0503c5c>] (__schedule_bug+0x48/0x5c)
[<c0503c5c>] (__schedule_bug+0x48/0x5c) from [<c0508608>] (__schedule+0x700/0x740)
[<c0508608>] (__schedule+0x700/0x740) from [<c007007c>] (__cond_resched+0x24/0x34)
[<c007007c>] (__cond_resched+0x24/0x34) from [<c05086dc>] (_cond_resched+0x3c/0x44)
[<c05086dc>] (_cond_resched+0x3c/0x44) from [<c0021f6c>] (do_alignment+0x178/0x78c)
[<c0021f6c>] (do_alignment+0x178/0x78c) from [<c00083e0>] (do_DataAbort+0x34/0x98)
[<c00083e0>] (do_DataAbort+0x34/0x98) from [<c0509a60>] (__dabt_svc+0x40/0x60)
Exception stack(0xc0763d70 to 0xc0763db8)
3d60: e97e805e e97e806e 2c000000 11000000
3d80: ea86bb00 0000002c 00000011 e97e807e c076d2a8 e97e805e e97e806e 0000002c
3da0: 3d000000 c0763dbc c04b98fc c02a8490 00000113 ffffffff
[<c0509a60>] (__dabt_svc+0x40/0x60) from [<c02a8490>] (__csum_ipv6_magic+0x8/0xc8)
Fix this by using probe_kernel_address() stead of __get_user().
Cc: <stable@vger.kernel.org>
Reported-by: Paolo Pisati <p.pisati@gmail.com>
Tested-by: Paolo Pisati <p.pisati@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
| -rw-r--r-- | arch/arm/mm/alignment.c | 11 |
1 files changed, 4 insertions, 7 deletions
diff --git a/arch/arm/mm/alignment.c b/arch/arm/mm/alignment.c index b820edaf3184..db26e2e543f4 100644 --- a/arch/arm/mm/alignment.c +++ b/arch/arm/mm/alignment.c @@ -749,7 +749,6 @@ do_alignment(unsigned long addr, unsigned int fsr, struct pt_regs *regs) unsigned long instr = 0, instrptr; int (*handler)(unsigned long addr, unsigned long instr, struct pt_regs *regs); unsigned int type; - mm_segment_t fs; unsigned int fault; u16 tinstr = 0; int isize = 4; @@ -760,16 +759,15 @@ do_alignment(unsigned long addr, unsigned int fsr, struct pt_regs *regs) instrptr = instruction_pointer(regs); - fs = get_fs(); - set_fs(KERNEL_DS); if (thumb_mode(regs)) { - fault = __get_user(tinstr, (u16 *)(instrptr & ~1)); + u16 *ptr = (u16 *)(instrptr & ~1); + fault = probe_kernel_address(ptr, tinstr); if (!fault) { if (cpu_architecture() >= CPU_ARCH_ARMv7 && IS_T32(tinstr)) { /* Thumb-2 32-bit */ u16 tinst2 = 0; - fault = __get_user(tinst2, (u16 *)(instrptr+2)); + fault = probe_kernel_address(ptr + 1, tinst2); instr = (tinstr << 16) | tinst2; thumb2_32b = 1; } else { @@ -778,8 +776,7 @@ do_alignment(unsigned long addr, unsigned int fsr, struct pt_regs *regs) } } } else - fault = __get_user(instr, (u32 *)instrptr); - set_fs(fs); + fault = probe_kernel_address(instrptr, instr); if (fault) { type = TYPE_FAULT; |