kernel/linux.git, branch v3.4.98

Linux 3.4.98

2014-07-09T17:52:25+00:00

mm: fix crashes from mbind() merging vmas

2014-07-09T17:51:22+00:00

commit d05f0cdcbe6388723f1900c549b4850360545201 upstream. In v2.6.34 commit 9d8cebd4bcd7 ("mm: fix mbind vma merge problem") introduced vma merging to mbind(), but it should have also changed the convention of passing start vma from queue_pages_range() (formerly check_range()) to new_vma_page(): vma merging may have already freed that structure, resulting in BUG at mm/mempolicy.c:1738 and probably worse crashes. Fixes: 9d8cebd4bcd7 ("mm: fix mbind vma merge problem") Reported-by: Naoya Horiguchi Tested-by: Naoya Horiguchi Signed-off-by: Hugh Dickins Acked-by: Christoph Lameter Cc: KOSAKI Motohiro Cc: Minchan Kim Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

hugetlb: fix copy_hugetlb_page_range() to handle migration/hwpoisoned entry

2014-07-09T17:51:22+00:00

commit 4a705fef986231a3e7a6b1a6d3c37025f021f49f upstream. There's a race between fork() and hugepage migration, as a result we try to "dereference" a swap entry as a normal pte, causing kernel panic. The cause of the problem is that copy_hugetlb_page_range() can't handle "swap entry" family (migration entry and hwpoisoned entry) so let's fix it. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Naoya Horiguchi Acked-by: Hugh Dickins Cc: Christoph Lameter Cc: [2.6.37+] Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

powerpc/sysfs: Disable writing to PURR in guest mode

2014-07-09T17:51:22+00:00

commit d1211af3049f4c9c1d8d4eb8f8098cc4f4f0d0c7 upstream. arch/powerpc/kernel/sysfs.c exports PURR with write permission. This may be valid for kernel in phyp mode. But writing to the file in guest mode causes crash due to a priviledge violation Signed-off-by: Madhavan Srinivasan Signed-off-by: Benjamin Herrenschmidt [Backported to 3.4: adjust context] Signed-off-by: Yijing Wang Signed-off-by: Greg Kroah-Hartman

ACPI video: ignore BIOS backlight value for HP dm4

2014-07-09T17:51:22+00:00

commit 771d09b3c4c45d4d534a83a68e6331b97fd82e15 upstream. On a HP Pavilion dm4 laptop the BIOS sets minimum backlight on boot, completely dimming the screen. Ignore this initial value for this machine. Signed-off-by: Gustavo Maciel Dias Vieira Signed-off-by: Rafael J. Wysocki Signed-off-by: Ben Hutchings [wyj: Backported to 3.4: adjust context] Signed-off-by: Yijing Wang Signed-off-by: Greg Kroah-Hartman

powerpc/pseries: Duplicate dtl entries sometimes sent to userspace

2014-07-09T17:51:22+00:00

commit 84b073868b9d9e754ae48b828337633d1b386482 upstream. When reading from the dispatch trace log (dtl) userspace interface, I sometimes see duplicate entries. One example: # hexdump -C dtl.out 00000000 07 04 00 0c 00 00 48 44 00 00 00 00 00 00 00 00 00000010 00 0c a0 b4 16 83 6d 68 00 00 00 00 00 00 00 00 00000020 00 00 00 00 10 00 13 50 80 00 00 00 00 00 d0 32 00000030 07 04 00 0c 00 00 48 44 00 00 00 00 00 00 00 00 00000040 00 0c a0 b4 16 83 6d 68 00 00 00 00 00 00 00 00 00000050 00 00 00 00 10 00 13 50 80 00 00 00 00 00 d0 32 The problem is in scan_dispatch_log() where we call dtl_consumer() but bail out before incrementing the index. To fix this I moved dtl_consumer() after the timebase comparison. Signed-off-by: Anton Blanchard Signed-off-by: Benjamin Herrenschmidt [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings Cc: Yijing Wang Signed-off-by: Greg Kroah-Hartman

powerpc/pseries/lparcfg: Fix possible overflow are more than 1026

2014-07-09T17:51:21+00:00

commit 5676005acf26ab7e924a8438ea4746e47d405762 upstream. need set '\0' for 'local_buffer'. SPLPAR_MAXLENGTH is 1026, RTAS_DATA_BUF_SIZE is 4096. so the contents of rtas_data_buf may truncated in memcpy. if contents are really truncated. the splpar_strlen is more than 1026. the next while loop checking will not find the end of buffer. that will cause memory access violation. Signed-off-by: Chen Gang Signed-off-by: Benjamin Herrenschmidt Signed-off-by: Ben Hutchings Cc: Yijing Wang Signed-off-by: Greg Kroah-Hartman

powerpc: Restore registers on error exit from csum_partial_copy_generic()

2014-07-09T17:51:21+00:00

commit 8f21bd0090052e740944f9397e2be5ac7957ded7 upstream. The csum_partial_copy_generic() function saves the PowerPC non-volatile r14, r15, and r16 registers for the main checksum-and-copy loop. Unfortunately, it fails to restore them upon error exit from this loop, which results in silent corruption of these registers in the presumably rare event of an access exception within that loop. This commit therefore restores these register on error exit from the loop. Signed-off-by: Paul E. McKenney Signed-off-by: Anton Blanchard Signed-off-by: Benjamin Herrenschmidt [bwh: Backported to 3.2: register name macros use lower-case 'r'] Signed-off-by: Ben Hutchings Cc: Yijing Wang Signed-off-by: Greg Kroah-Hartman

powerpc: Don't Oops when accessing /proc/powerpc/lparcfg without hypervisor

2014-07-09T17:51:21+00:00

commit f5f6cbb61610b7bf9d9d96db9c3979d62a424bab upstream. /proc/powerpc/lparcfg is an ancient facility (though still actively used) which allows access to some informations relative to the partition when running underneath a PAPR compliant hypervisor. It makes no sense on non-pseries machines. However, currently, not only can it be created on these if the kernel has pseries support, but accessing it on such a machine will crash due to trying to do hypervisor calls. In fact, it should also not do HV calls on older pseries that didn't have an hypervisor either. Finally, it has the plumbing to be a module but is a "bool" Kconfig option. This fixes the whole lot by turning it into a machine_device_initcall that is only created on pseries, and adding the necessary hypervisor check before calling the H_GET_EM_PARMS hypercall Signed-off-by: Benjamin Herrenschmidt [bwh: Backported to 3.2: lparcfg_cleanup() was a bit different] Signed-off-by: Ben Hutchings Cc: Yijing Wang Signed-off-by: Greg Kroah-Hartman

powerpc/smp: Section mismatch from smp_release_cpus to __initdata spinning_secondaries

2014-07-09T17:51:21+00:00

commit 8246aca7058f3f2c2ae503081777965cd8df7b90 upstream. the smp_release_cpus is a normal funciton and called in normal environments, but it calls the __initdata spinning_secondaries. need modify spinning_secondaries to match smp_release_cpus. the related warning: (the linker report boot_paca.33377, but it should be spinning_secondaries) ----------------------------------------------------------------------------- WARNING: arch/powerpc/kernel/built-in.o(.text+0x23176): Section mismatch in reference from the function .smp_release_cpus() to the variable .init.data:boot_paca.33377 The function .smp_release_cpus() references the variable __initdata boot_paca.33377. This is often because .smp_release_cpus lacks a __initdata annotation or the annotation of boot_paca.33377 is wrong. WARNING: arch/powerpc/kernel/built-in.o(.text+0x231fe): Section mismatch in reference from the function .smp_release_cpus() to the variable .init.data:boot_paca.33377 The function .smp_release_cpus() references the variable __initdata boot_paca.33377. This is often because .smp_release_cpus lacks a __initdata annotation or the annotation of boot_paca.33377 is wrong. ----------------------------------------------------------------------------- Signed-off-by: Chen Gang Signed-off-by: Benjamin Herrenschmidt Signed-off-by: Ben Hutchings Cc: Yijing Wang Signed-off-by: Greg Kroah-Hartman