Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > linux.kernel > #1533110

[PATCH 4.4 15/21] parisc: Fix race in pci-dma.c

Show all headers | View raw

4.4-stable review patch.  If anyone has any objections, please let me know.

------------------

From: John David Anglin <dave.anglin@bell.net>

commit c0452fb9fb8f49c7d68ab9fa0ad092016be7b45f upstream.

We are still troubled by occasional random segmentation faults and
memory memory corruption on SMP machines.  The causes quite a few
package builds to fail on the Debian buildd machines for parisc.  When
gcc-6 failed to build three times in a row, I looked again at the TLB
related code.  I found a couple of issues.  This is the first.

In general, we need to ensure page table updates and corresponding TLB
purges are atomic.  The attached patch fixes an instance in pci-dma.c
where the page table update was not guarded by the TLB lock.

Tested on rp3440 and c8000.  So far, no further random segmentation
faults have been observed.

Signed-off-by: John David Anglin  <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 arch/parisc/kernel/pci-dma.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/arch/parisc/kernel/pci-dma.c
+++ b/arch/parisc/kernel/pci-dma.c
@@ -95,8 +95,8 @@ static inline int map_pte_uncached(pte_t
 
 		if (!pte_none(*pte))
 			printk(KERN_ERR "map_pte_uncached: page already exists\n");
-		set_pte(pte, __mk_pte(*paddr_ptr, PAGE_KERNEL_UNC));
 		purge_tlb_start(flags);
+		set_pte(pte, __mk_pte(*paddr_ptr, PAGE_KERNEL_UNC));
 		pdtlb_kernel(orig_vaddr);
 		purge_tlb_end(flags);
 		vaddr += PAGE_SIZE;

Back to linux.kernel | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread

Thread

[PATCH 4.4 00/21] 4.4.36-stable review Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-11-30 10:30 +0100
  [PATCH 4.4 07/21] USB: serial: ftdi_sio: add support for TI CC3200 LaunchPad Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-11-30 10:30 +0100
  [PATCH 4.4 15/21] parisc: Fix race in pci-dma.c Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-11-30 10:40 +0100
  [PATCH 4.4 06/21] USB: serial: cp210x: add ID for the Zone DPMX Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-11-30 10:40 +0100
  [PATCH 4.4 21/21] mei: fix return value on disconnection Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-11-30 10:40 +0100
  [PATCH 4.4 17/21] mpi: Fix NULL ptr dereference in mpi_powm() [ver #3] Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-11-30 10:40 +0100
  [PATCH 4.4 20/21] mei: me: fix place for kaby point device ids. Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-11-30 10:40 +0100
  [PATCH 4.4 05/21] usb: chipidea: move the lock initialization to core file Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-11-30 10:40 +0100
  [PATCH 4.4 19/21] mei: me: disable driver on SPT SPS firmware Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-11-30 11:00 +0100
  [PATCH 4.4 08/21] Fix USB CB/CBI storage devices with CONFIG_VMAP_STACK=y Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-11-30 11:00 +0100
  [PATCH 4.4 16/21] parisc: Also flush data TLB in flush_icache_page_asm Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-11-30 11:00 +0100
  [PATCH 4.4 12/21] apparmor: fix change_hat not finding hat after policy replacement Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-11-30 11:10 +0100
  [PATCH 4.4 09/21] scsi: mpt3sas: Fix secure erase premature termination Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-11-30 11:10 +0100
  [PATCH 4.4 10/21] tile: avoid using clocksource_cyc2ns with absolute cycle count Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-11-30 11:10 +0100
  [PATCH 4.4 14/21] parisc: Fix races in parisc_setup_cache_timing() Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-11-30 11:10 +0100
  [PATCH 4.4 13/21] NFSv4.x: hide array-bounds warning Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-11-30 11:10 +0100
  [PATCH 4.4 11/21] cfg80211: limit scan results cache size Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-11-30 11:10 +0100
  Re: [PATCH 4.4 00/21] 4.4.36-stable review Andre Noll <maan@tuebingen.mpg.de> - 2016-11-30 14:50 +0100
    Re: [PATCH 4.4 00/21] 4.4.36-stable review Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-11-30 15:00 +0100
      Re: [PATCH 4.4 00/21] 4.4.36-stable review Andre Noll <maan@tuebingen.mpg.de> - 2016-11-30 15:10 +0100
        Re: [PATCH 4.4 00/21] 4.4.36-stable review Eric Dumazet <edumazet@google.com> - 2016-11-30 15:30 +0100
          Re: [PATCH 4.4 00/21] 4.4.36-stable review Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-11-30 15:40 +0100
        Re: [PATCH 4.4 00/21] 4.4.36-stable review David Miller <davem@davemloft.net> - 2016-11-30 16:00 +0100
          Re: [PATCH 4.4 00/21] 4.4.36-stable review Andre Noll <maan@tuebingen.mpg.de> - 2016-11-30 16:20 +0100
      Re: [PATCH 4.4 00/21] 4.4.36-stable review David Miller <davem@davemloft.net> - 2016-11-30 16:00 +0100
        Re: [PATCH 4.4 00/21] 4.4.36-stable review Greg KH <gregkh@linuxfoundation.org> - 2016-11-30 16:40 +0100
  Re: [PATCH 4.4 00/21] 4.4.36-stable review Shuah Khan <shuah.kh@samsung.com> - 2016-11-30 17:10 +0100
  Re: [PATCH 4.4 00/21] 4.4.36-stable review Guenter Roeck <linux@roeck-us.net> - 2016-12-01 00:30 +0100

csiph-web