Linux v3.4-9208-gaf56e0a

This commit is contained in:
Josh Boyer 2012-05-31 08:54:01 -04:00
parent ad6b974304
commit 478adfe8fb
6 changed files with 26 additions and 294 deletions

View File

@ -3333,7 +3333,7 @@ CONFIG_MFD_VX855=m
CONFIG_MFD_SM501=m CONFIG_MFD_SM501=m
CONFIG_MFD_SM501_GPIO=y CONFIG_MFD_SM501_GPIO=y
# CONFIG_MFD_TC6393XB is not set # CONFIG_MFD_TC6393XB is not set
CONFIG_MFD_WM8400=m # CONFIG_MFD_WM8400 is not set
# CONFIG_MFD_WM8350_I2C is not set # CONFIG_MFD_WM8350_I2C is not set
# CONFIG_MFD_WM8350 is not set # CONFIG_MFD_WM8350 is not set
# CONFIG_MFD_WM831X is not set # CONFIG_MFD_WM831X is not set
@ -3342,6 +3342,7 @@ CONFIG_MFD_WM8400=m
# CONFIG_MFD_WM8994 is not set # CONFIG_MFD_WM8994 is not set
# CONFIG_MFD_88PM860X is not set # CONFIG_MFD_88PM860X is not set
# CONFIG_LPC_SCH is not set # CONFIG_LPC_SCH is not set
# CONFIG_LPC_ICH is not set
# CONFIG_HTC_I2CPLD is not set # CONFIG_HTC_I2CPLD is not set
# CONFIG_MFD_MAX8925 is not set # CONFIG_MFD_MAX8925 is not set
# CONFIG_MFD_ASIC3 is not set # CONFIG_MFD_ASIC3 is not set
@ -3358,6 +3359,8 @@ CONFIG_MFD_WM8400=m
# CONFIG_MFD_TC3589X is not set # CONFIG_MFD_TC3589X is not set
# CONFIG_MFD_WL1273_CORE is not set # CONFIG_MFD_WL1273_CORE is not set
# CONFIG_MFD_TPS65217 is not set # CONFIG_MFD_TPS65217 is not set
# CONFIG_MFD_LM3533 is not set
# CONFIG_MFD_MC13XXX_I2C is not set
# #
# File systems # File systems
@ -3494,6 +3497,7 @@ CONFIG_CUSE=m
# #
CONFIG_NETWORK_FILESYSTEMS=y CONFIG_NETWORK_FILESYSTEMS=y
CONFIG_NFS_FS=m CONFIG_NFS_FS=m
CONFIG_NFS_V2=y
CONFIG_NFS_V3=y CONFIG_NFS_V3=y
CONFIG_NFS_V3_ACL=y CONFIG_NFS_V3_ACL=y
CONFIG_NFS_V4=y CONFIG_NFS_V4=y
@ -3682,6 +3686,7 @@ CONFIG_LOCKUP_DETECTOR=y
CONFIG_ATOMIC64_SELFTEST=y CONFIG_ATOMIC64_SELFTEST=y
CONFIG_MEMORY_FAILURE=y CONFIG_MEMORY_FAILURE=y
CONFIG_HWPOISON_INJECT=m CONFIG_HWPOISON_INJECT=m
CONFIG_CROSS_MEMORY_ATTACH=y
# CONFIG_DEBUG_SECTION_MISMATCH is not set # CONFIG_DEBUG_SECTION_MISMATCH is not set
# CONFIG_BACKTRACE_SELF_TEST is not set # CONFIG_BACKTRACE_SELF_TEST is not set
CONFIG_LATENCYTOP=y CONFIG_LATENCYTOP=y
@ -3977,6 +3982,7 @@ CONFIG_LEDS_TRIGGER_IDE_DISK=y
CONFIG_LEDS_TRIGGER_HEARTBEAT=m CONFIG_LEDS_TRIGGER_HEARTBEAT=m
CONFIG_LEDS_TRIGGER_BACKLIGHT=m CONFIG_LEDS_TRIGGER_BACKLIGHT=m
CONFIG_LEDS_TRIGGER_DEFAULT_ON=m CONFIG_LEDS_TRIGGER_DEFAULT_ON=m
CONFIG_LEDS_TRIGGER_TRANSIENT=m
CONFIG_LEDS_ALIX2=m CONFIG_LEDS_ALIX2=m
CONFIG_LEDS_CLEVO_MAIL=m CONFIG_LEDS_CLEVO_MAIL=m
CONFIG_LEDS_INTEL_SS4200=m CONFIG_LEDS_INTEL_SS4200=m

View File

@ -357,6 +357,9 @@ CONFIG_TOSHIBA_BT_RFKILL=m
CONFIG_VGA_SWITCHEROO=y CONFIG_VGA_SWITCHEROO=y
CONFIG_LPC_SCH=m CONFIG_LPC_SCH=m
CONFIG_LPC_ICH=m
CONFIG_GPIO_ICH=m
CONFIG_PCI_CNB20LE_QUIRK=y CONFIG_PCI_CNB20LE_QUIRK=y

View File

@ -1,8 +1,8 @@
diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index 71c7096..5defdd5 100644 index 296cfc2..516e1e2 100644
--- a/drivers/gpu/drm/i915/intel_dp.c --- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c +++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -347,7 +347,7 @@ intel_dp_check_edp(struct intel_dp *intel_dp) @@ -350,7 +350,7 @@ intel_dp_check_edp(struct intel_dp *intel_dp)
if (!is_edp(intel_dp)) if (!is_edp(intel_dp))
return; return;
if (!ironlake_edp_have_panel_power(intel_dp) && !ironlake_edp_have_panel_vdd(intel_dp)) { if (!ironlake_edp_have_panel_power(intel_dp) && !ironlake_edp_have_panel_vdd(intel_dp)) {
@ -11,7 +11,7 @@ index 71c7096..5defdd5 100644
DRM_DEBUG_KMS("Status 0x%08x Control 0x%08x\n", DRM_DEBUG_KMS("Status 0x%08x Control 0x%08x\n",
I915_READ(PCH_PP_STATUS), I915_READ(PCH_PP_STATUS),
I915_READ(PCH_PP_CONTROL)); I915_READ(PCH_PP_CONTROL));
@@ -397,7 +397,7 @@ intel_dp_aux_ch(struct intel_dp *intel_dp, @@ -400,7 +400,7 @@ intel_dp_aux_ch(struct intel_dp *intel_dp,
} }
if (try == 3) { if (try == 3) {
@ -20,7 +20,7 @@ index 71c7096..5defdd5 100644
I915_READ(ch_ctl)); I915_READ(ch_ctl));
return -EBUSY; return -EBUSY;
} }
@@ -1018,8 +1018,8 @@ static void ironlake_edp_panel_vdd_on(struct intel_dp *intel_dp) @@ -1024,8 +1024,8 @@ static void ironlake_edp_panel_vdd_on(struct intel_dp *intel_dp)
return; return;
DRM_DEBUG_KMS("Turn eDP VDD on\n"); DRM_DEBUG_KMS("Turn eDP VDD on\n");
@ -31,7 +31,7 @@ index 71c7096..5defdd5 100644
intel_dp->want_panel_vdd = true; intel_dp->want_panel_vdd = true;
@@ -1084,7 +1084,8 @@ static void ironlake_edp_panel_vdd_off(struct intel_dp *intel_dp, bool sync) @@ -1090,7 +1090,8 @@ static void ironlake_edp_panel_vdd_off(struct intel_dp *intel_dp, bool sync)
return; return;
DRM_DEBUG_KMS("Turn eDP VDD off %d\n", intel_dp->want_panel_vdd); DRM_DEBUG_KMS("Turn eDP VDD off %d\n", intel_dp->want_panel_vdd);
@ -41,14 +41,13 @@ index 71c7096..5defdd5 100644
intel_dp->want_panel_vdd = false; intel_dp->want_panel_vdd = false;
@@ -1154,7 +1155,9 @@ static void ironlake_edp_panel_off(struct intel_dp *intel_dp) @@ -1160,7 +1161,8 @@ static void ironlake_edp_panel_off(struct intel_dp *intel_dp)
DRM_DEBUG_KMS("Turn eDP power off\n"); DRM_DEBUG_KMS("Turn eDP power off\n");
- WARN(intel_dp->want_panel_vdd, "Cannot turn power off while VDD is on\n"); - WARN(!intel_dp->want_panel_vdd, "Need VDD to turn off panel\n");
+ if (intel_dp->want_panel_vdd) + if (!intel_dp->want_panel_vdd)
+ DRM_ERROR("Cannot turn power off while VDD is on\n"); + DRM_ERROR("Need VDD to turn off panel\n");
+
ironlake_panel_vdd_off_sync(intel_dp); /* finish any pending work */
pp = ironlake_get_pp_control(dev_priv); pp = ironlake_get_pp_control(dev_priv);
pp &= ~(POWER_TARGET_ON | PANEL_POWER_RESET | EDP_BLC_ENABLE);

View File

@ -62,7 +62,7 @@ Summary: The Linux kernel
# For non-released -rc kernels, this will be appended after the rcX and # For non-released -rc kernels, this will be appended after the rcX and
# gitX tags, so a 3 here would become part of release "0.rcX.gitX.3" # gitX tags, so a 3 here would become part of release "0.rcX.gitX.3"
# #
%global baserelease 2 %global baserelease 1
%global fedora_build %{baserelease} %global fedora_build %{baserelease}
# base_sublevel is the kernel version we're starting with and patching # base_sublevel is the kernel version we're starting with and patching
@ -95,7 +95,7 @@ Summary: The Linux kernel
# The rc snapshot level # The rc snapshot level
%define rcrev 0 %define rcrev 0
# The git snapshot level # The git snapshot level
%define gitrev 9 %define gitrev 10
# Set rpm version accordingly # Set rpm version accordingly
%define rpmversion 3.%{upstream_sublevel}.0 %define rpmversion 3.%{upstream_sublevel}.0
%endif %endif
@ -749,9 +749,6 @@ Patch22000: weird-root-dentry-name-debug.patch
#selinux ptrace child permissions #selinux ptrace child permissions
Patch22001: selinux-apply-different-permission-to-ptrace-child.patch Patch22001: selinux-apply-different-permission-to-ptrace-child.patch
#rhbz 822825 822821 CVE-2012-2372
Patch22021: mm-pmd_read_atomic-fix-32bit-PAE-pmd-walk-vs-pmd_populate-SMP-race-condition.patch
# END OF PATCH DEFINITIONS # END OF PATCH DEFINITIONS
%endif %endif
@ -1447,9 +1444,6 @@ ApplyPatch selinux-apply-different-permission-to-ptrace-child.patch
#Highbank clock functions #Highbank clock functions
ApplyPatch highbank-export-clock-functions.patch ApplyPatch highbank-export-clock-functions.patch
#rhbz 822825 822821 CVE-2012-2372
ApplyPatch mm-pmd_read_atomic-fix-32bit-PAE-pmd-walk-vs-pmd_populate-SMP-race-condition.patch
# END OF PATCH APPLICATIONS # END OF PATCH APPLICATIONS
%endif %endif
@ -2300,6 +2294,9 @@ fi
# ||----w | # ||----w |
# || || # || ||
%changelog %changelog
* Thu May 31 2012 Josh Boyer <jwboyer@redhat.com> - 3.5.0-0.rc0.git10.1
- Linux v3.4-9208-gaf56e0a
* Wed May 30 2012 Josh Boyer <jwboyer@redhat.com> * Wed May 30 2012 Josh Boyer <jwboyer@redhat.com>
- modsign: Fix 32bit ELF table interpretation from David Howells (rhbz 825944) - modsign: Fix 32bit ELF table interpretation from David Howells (rhbz 825944)

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@ -1,272 +0,0 @@
Path: news.gmane.org!not-for-mail
From: Andrea Arcangeli <aarcange@redhat.com>
Newsgroups: gmane.linux.kernel.mm
Subject: [PATCH] mm: pmd_read_atomic: fix 32bit PAE pmd walk vs pmd_populate SMP race condition
Date: Thu, 24 May 2012 01:39:01 +0200
Lines: 208
Approved: news@gmane.org
Message-ID: <1337816341-30743-1-git-send-email-aarcange@redhat.com>
References: <20120518230028.GF32479@redhat.com>
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Cc: Andrew Morton <akpm@linux-foundation.org>, Mel Gorman <mgorman@suse.de>,
Hugh Dickins <hughd@google.com>, Larry Woodman <lwoodman@redhat.com>,
Petr Matousek <pmatouse@redhat.com>,
Ulrich Obergfell <uobergfe@redhat.com>, Rik van Riel <riel@redhat.com>
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When holding the mmap_sem for reading, pmd_offset_map_lock should only
run on a pmd_t that has been read atomically from the pmdp
pointer, otherwise we may read only half of it leading to this crash.
PID: 11679 TASK: f06e8000 CPU: 3 COMMAND: "do_race_2_panic"
#0 [f06a9dd8] crash_kexec at c049b5ec
#1 [f06a9e2c] oops_end at c083d1c2
#2 [f06a9e40] no_context at c0433ded
#3 [f06a9e64] bad_area_nosemaphore at c043401a
#4 [f06a9e6c] __do_page_fault at c0434493
#5 [f06a9eec] do_page_fault at c083eb45
#6 [f06a9f04] error_code (via page_fault) at c083c5d5
EAX: 01fb470c EBX: fff35000 ECX: 00000003 EDX: 00000100 EBP:
00000000
DS: 007b ESI: 9e201000 ES: 007b EDI: 01fb4700 GS: 00e0
CS: 0060 EIP: c083bc14 ERR: ffffffff EFLAGS: 00010246
#7 [f06a9f38] _spin_lock at c083bc14
#8 [f06a9f44] sys_mincore at c0507b7d
#9 [f06a9fb0] system_call at c083becd
start len
EAX: ffffffda EBX: 9e200000 ECX: 00001000 EDX: 6228537f
DS: 007b ESI: 00000000 ES: 007b EDI: 003d0f00
SS: 007b ESP: 62285354 EBP: 62285388 GS: 0033
CS: 0073 EIP: 00291416 ERR: 000000da EFLAGS: 00000286
This should be a longstanding bug affecting x86 32bit PAE without
THP. Only archs with 64bit large pmd_t and 32bit unsigned long should
be affected.
With THP enabled the barrier() in
pmd_none_or_trans_huge_or_clear_bad() would partly hide the bug when
the pmd transition from none to stable, by forcing a re-read of the
*pmd in pmd_offset_map_lock, but when THP is enabled a new set of
problem arises by the fact could then transition freely in any of the
none, pmd_trans_huge or pmd_trans_stable states. So making the barrier
in pmd_none_or_trans_huge_or_clear_bad() unconditional isn't good idea
and it would be a flakey solution.
This should be fully fixed by introducing a pmd_read_atomic that reads
the pmd in order with THP disabled, or by reading the pmd atomically
with cmpxchg8b with THP enabled.
Luckily this new race condition only triggers in the places that must
already be covered by pmd_none_or_trans_huge_or_clear_bad() so the fix
is localized there but this bug is not related to THP.
NOTE: this can trigger on x86 32bit systems with PAE enabled with more
than 4G of ram, otherwise the high part of the pmd will never risk to
be truncated because it would be zero at all times, in turn so hiding
the SMP race.
This bug was discovered and fully debugged by Ulrich, quote:
----
[..]
pmd_none_or_trans_huge_or_clear_bad() loads the content of edx and
eax.
496 static inline int pmd_none_or_trans_huge_or_clear_bad(pmd_t
*pmd)
497 {
498 /* depend on compiler for an atomic pmd read */
499 pmd_t pmdval = *pmd;
// edi = pmd pointer
0xc0507a74 <sys_mincore+548>: mov 0x8(%esp),%edi
...
// edx = PTE page table high address
0xc0507a84 <sys_mincore+564>: mov 0x4(%edi),%edx
...
// eax = PTE page table low address
0xc0507a8e <sys_mincore+574>: mov (%edi),%eax
[..]
Please note that the PMD is not read atomically. These are two "mov"
instructions where the high order bits of the PMD entry are fetched
first. Hence, the above machine code is prone to the following race.
- The PMD entry {high|low} is 0x0000000000000000.
The "mov" at 0xc0507a84 loads 0x00000000 into edx.
- A page fault (on another CPU) sneaks in between the two "mov"
instructions and instantiates the PMD.
- The PMD entry {high|low} is now 0x00000003fda38067.
The "mov" at 0xc0507a8e loads 0xfda38067 into eax.
----
Reported-by: Ulrich Obergfell <uobergfe@redhat.com>
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
---
arch/x86/include/asm/pgtable-3level.h | 50 +++++++++++++++++++++++++++++++++
include/asm-generic/pgtable.h | 22 +++++++++++++-
2 files changed, 70 insertions(+), 2 deletions(-)
diff --git a/arch/x86/include/asm/pgtable-3level.h b/arch/x86/include/asm/pgtable-3level.h
index effff47..43876f1 100644
--- a/arch/x86/include/asm/pgtable-3level.h
+++ b/arch/x86/include/asm/pgtable-3level.h
@@ -31,6 +31,56 @@ static inline void native_set_pte(pte_t *ptep, pte_t pte)
ptep->pte_low = pte.pte_low;
}
+#define pmd_read_atomic pmd_read_atomic
+/*
+ * pte_offset_map_lock on 32bit PAE kernels was reading the pmd_t with
+ * a "*pmdp" dereference done by gcc. Problem is, in certain places
+ * where pte_offset_map_lock is called, concurrent page faults are
+ * allowed, if the mmap_sem is hold for reading. An example is mincore
+ * vs page faults vs MADV_DONTNEED. On the page fault side
+ * pmd_populate rightfully does a set_64bit, but if we're reading the
+ * pmd_t with a "*pmdp" on the mincore side, a SMP race can happen
+ * because gcc will not read the 64bit of the pmd atomically. To fix
+ * this all places running pmd_offset_map_lock() while holding the
+ * mmap_sem in read mode, shall read the pmdp pointer using this
+ * function to know if the pmd is null nor not, and in turn to know if
+ * they can run pmd_offset_map_lock or pmd_trans_huge or other pmd
+ * operations.
+ *
+ * Without THP if the mmap_sem is hold for reading, the
+ * pmd can only transition from null to not null while pmd_read_atomic runs.
+ * So there's no need of literally reading it atomically.
+ *
+ * With THP if the mmap_sem is hold for reading, the pmd can become
+ * THP or null or point to a pte (and in turn become "stable") at any
+ * time under pmd_read_atomic, so it's mandatory to read it atomically
+ * with cmpxchg8b.
+ */
+#ifndef CONFIG_TRANSPARENT_HUGEPAGE
+static inline pmd_t pmd_read_atomic(pmd_t *pmdp)
+{
+ pmdval_t ret;
+ u32 *tmp = (u32 *)pmdp;
+
+ ret = (pmdval_t) (*tmp);
+ if (ret) {
+ /*
+ * If the low part is null, we must not read the high part
+ * or we can end up with a partial pmd.
+ */
+ smp_rmb();
+ ret |= ((pmdval_t)*(tmp + 1)) << 32;
+ }
+
+ return (pmd_t) { ret };
+}
+#else /* CONFIG_TRANSPARENT_HUGEPAGE */
+static inline pmd_t pmd_read_atomic(pmd_t *pmdp)
+{
+ return (pmd_t) { atomic64_read((atomic64_t *)pmdp) };
+}
+#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
+
static inline void native_set_pte_atomic(pte_t *ptep, pte_t pte)
{
set_64bit((unsigned long long *)(ptep), native_pte_val(pte));
diff --git a/include/asm-generic/pgtable.h b/include/asm-generic/pgtable.h
index 125c54e..fa596d9 100644
--- a/include/asm-generic/pgtable.h
+++ b/include/asm-generic/pgtable.h
@@ -446,6 +446,18 @@ static inline int pmd_write(pmd_t pmd)
#endif /* __HAVE_ARCH_PMD_WRITE */
#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
+#ifndef pmd_read_atomic
+static inline pmd_t pmd_read_atomic(pmd_t *pmdp)
+{
+ /*
+ * Depend on compiler for an atomic pmd read. NOTE: this is
+ * only going to work, if the pmdval_t isn't larger than
+ * an unsigned long.
+ */
+ return *pmdp;
+}
+#endif
+
/*
* This function is meant to be used by sites walking pagetables with
* the mmap_sem hold in read mode to protect against MADV_DONTNEED and
@@ -459,11 +471,17 @@ static inline int pmd_write(pmd_t pmd)
* undefined so behaving like if the pmd was none is safe (because it
* can return none anyway). The compiler level barrier() is critically
* important to compute the two checks atomically on the same pmdval.
+ *
+ * For 32bit kernels with a 64bit large pmd_t this automatically takes
+ * care of reading the pmd atomically to avoid SMP race conditions
+ * against pmd_populate() when the mmap_sem is hold for reading by the
+ * caller (a special atomic read not done by "gcc" as in the generic
+ * version above, is also needed when THP is disabled because the page
+ * fault can populate the pmd from under us).
*/
static inline int pmd_none_or_trans_huge_or_clear_bad(pmd_t *pmd)
{
- /* depend on compiler for an atomic pmd read */
- pmd_t pmdval = *pmd;
+ pmd_t pmdval = pmd_read_atomic(pmd);
/*
* The barrier will stabilize the pmdval in a register or on
* the stack so that it will stop changing under the code.
--
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View File

@ -1,3 +1,2 @@
967f72983655e2479f951195953e8480 linux-3.4.tar.xz 967f72983655e2479f951195953e8480 linux-3.4.tar.xz
90c5749495311b1d7d935923d5f16109 patch-3.4-git8.xz 11275fd70893f1a51c1fca34601eadbd patch-3.4-git10.xz
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