This is a note to let you know that I've just added the patch titled
net_sched: get rid of rcu_barrier() in tcf_block_put_ext()
to the 4.14-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
net_sched-get-rid-of-rcu_barrier-in-tcf_block_put_ext.patch
and it can be found in the queue-4.14 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From efbf78973978b0d25af59bc26c8013a942af6e64 Mon Sep 17 00:00:00 2001
From: Cong Wang <xiyou.wangcong(a)gmail.com>
Date: Mon, 4 Dec 2017 10:48:18 -0800
Subject: net_sched: get rid of rcu_barrier() in tcf_block_put_ext()
From: Cong Wang <xiyou.wangcong(a)gmail.com>
commit efbf78973978b0d25af59bc26c8013a942af6e64 upstream.
Both Eric and Paolo noticed the rcu_barrier() we use in
tcf_block_put_ext() could be a performance bottleneck when
we have a lot of tc classes.
Paolo provided the following to demonstrate the issue:
tc qdisc add dev lo root htb
for I in `seq 1 1000`; do
tc class add dev lo parent 1: classid 1:$I htb rate 100kbit
tc qdisc add dev lo parent 1:$I handle $((I + 1)): htb
for J in `seq 1 10`; do
tc filter add dev lo parent $((I + 1)): u32 match ip src 1.1.1.$J
done
done
time tc qdisc del dev root
real 0m54.764s
user 0m0.023s
sys 0m0.000s
The rcu_barrier() there is to ensure we free the block after all chains
are gone, that is, to queue tcf_block_put_final() at the tail of workqueue.
We can achieve this ordering requirement by refcnt'ing tcf block instead,
that is, the tcf block is freed only when the last chain in this block is
gone. This also simplifies the code.
Paolo reported after this patch we get:
real 0m0.017s
user 0m0.000s
sys 0m0.017s
Tested-by: Paolo Abeni <pabeni(a)redhat.com>
Cc: Eric Dumazet <edumazet(a)google.com>
Cc: Jiri Pirko <jiri(a)mellanox.com>
Cc: Jamal Hadi Salim <jhs(a)mojatatu.com>
Signed-off-by: Cong Wang <xiyou.wangcong(a)gmail.com>
Signed-off-by: David S. Miller <davem(a)davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
include/net/sch_generic.h | 1 -
net/sched/cls_api.c | 29 +++++++++--------------------
2 files changed, 9 insertions(+), 21 deletions(-)
--- a/include/net/sch_generic.h
+++ b/include/net/sch_generic.h
@@ -273,7 +273,6 @@ struct tcf_chain {
struct tcf_block {
struct list_head chain_list;
- struct work_struct work;
};
static inline void qdisc_cb_private_validate(const struct sk_buff *skb, int sz)
--- a/net/sched/cls_api.c
+++ b/net/sched/cls_api.c
@@ -211,8 +211,12 @@ static void tcf_chain_flush(struct tcf_c
static void tcf_chain_destroy(struct tcf_chain *chain)
{
+ struct tcf_block *block = chain->block;
+
list_del(&chain->list);
kfree(chain);
+ if (list_empty(&block->chain_list))
+ kfree(block);
}
static void tcf_chain_hold(struct tcf_chain *chain)
@@ -276,26 +280,12 @@ err_chain_create:
}
EXPORT_SYMBOL(tcf_block_get);
-static void tcf_block_put_final(struct work_struct *work)
-{
- struct tcf_block *block = container_of(work, struct tcf_block, work);
- struct tcf_chain *chain, *tmp;
-
- rtnl_lock();
-
- /* At this point, all the chains should have refcnt == 1. */
- list_for_each_entry_safe(chain, tmp, &block->chain_list, list)
- tcf_chain_put(chain);
- rtnl_unlock();
- kfree(block);
-}
-
/* XXX: Standalone actions are not allowed to jump to any chain, and bound
* actions should be all removed after flushing.
*/
void tcf_block_put(struct tcf_block *block)
{
- struct tcf_chain *chain;
+ struct tcf_chain *chain, *tmp;
if (!block)
return;
@@ -310,12 +300,11 @@ void tcf_block_put(struct tcf_block *blo
list_for_each_entry(chain, &block->chain_list, list)
tcf_chain_flush(chain);
- INIT_WORK(&block->work, tcf_block_put_final);
- /* Wait for RCU callbacks to release the reference count and make
- * sure their works have been queued before this.
+ /* At this point, all the chains should have refcnt >= 1. Block will be
+ * freed after all chains are gone.
*/
- rcu_barrier();
- tcf_queue_work(&block->work);
+ list_for_each_entry_safe(chain, tmp, &block->chain_list, list)
+ tcf_chain_put(chain);
}
EXPORT_SYMBOL(tcf_block_put);
Patches currently in stable-queue which might be from xiyou.wangcong(a)gmail.com are
queue-4.14/net_sched-get-rid-of-rcu_barrier-in-tcf_block_put_ext.patch
queue-4.14/net-sched-crash-on-blocks-with-goto-chain-action.patch
queue-4.14/net-sched-fix-use-after-free-in-tcf_block_put_ext.patch
queue-4.14/net-sched-fix-crash-when-deleting-secondary-chains.patch
This is a note to let you know that I've just added the patch titled
net: sched: fix use-after-free in tcf_block_put_ext
to the 4.14-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
net-sched-fix-use-after-free-in-tcf_block_put_ext.patch
and it can be found in the queue-4.14 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From df45bf84e4f5a48f23d4b1a07d21d566e8b587b2 Mon Sep 17 00:00:00 2001
From: Jiri Pirko <jiri(a)mellanox.com>
Date: Fri, 8 Dec 2017 19:27:27 +0100
Subject: net: sched: fix use-after-free in tcf_block_put_ext
From: Jiri Pirko <jiri(a)mellanox.com>
commit df45bf84e4f5a48f23d4b1a07d21d566e8b587b2 upstream.
Since the block is freed with last chain being put, once we reach the
end of iteration of list_for_each_entry_safe, the block may be
already freed. I'm hitting this only by creating and deleting clsact:
[ 202.171952] ==================================================================
[ 202.180182] BUG: KASAN: use-after-free in tcf_block_put_ext+0x240/0x390
[ 202.187590] Read of size 8 at addr ffff880225539a80 by task tc/796
[ 202.194508]
[ 202.196185] CPU: 0 PID: 796 Comm: tc Not tainted 4.15.0-rc2jiri+ #5
[ 202.203200] Hardware name: Mellanox Technologies Ltd. "MSN2100-CB2F"/"SA001017", BIOS 5.6.5 06/07/2016
[ 202.213613] Call Trace:
[ 202.216369] dump_stack+0xda/0x169
[ 202.220192] ? dma_virt_map_sg+0x147/0x147
[ 202.224790] ? show_regs_print_info+0x54/0x54
[ 202.229691] ? tcf_chain_destroy+0x1dc/0x250
[ 202.234494] print_address_description+0x83/0x3d0
[ 202.239781] ? tcf_block_put_ext+0x240/0x390
[ 202.244575] kasan_report+0x1ba/0x460
[ 202.248707] ? tcf_block_put_ext+0x240/0x390
[ 202.253518] tcf_block_put_ext+0x240/0x390
[ 202.258117] ? tcf_chain_flush+0x290/0x290
[ 202.262708] ? qdisc_hash_del+0x82/0x1a0
[ 202.267111] ? qdisc_hash_add+0x50/0x50
[ 202.271411] ? __lock_is_held+0x5f/0x1a0
[ 202.275843] clsact_destroy+0x3d/0x80 [sch_ingress]
[ 202.281323] qdisc_destroy+0xcb/0x240
[ 202.285445] qdisc_graft+0x216/0x7b0
[ 202.289497] tc_get_qdisc+0x260/0x560
Fix this by holding the block also by chain 0 and put chain 0
explicitly, out of the list_for_each_entry_safe loop at the very
end of tcf_block_put_ext.
Fixes: efbf78973978 ("net_sched: get rid of rcu_barrier() in tcf_block_put_ext()")
Signed-off-by: Jiri Pirko <jiri(a)mellanox.com>
Signed-off-by: David S. Miller <davem(a)davemloft.net>
Cc: Cong Wang <xiyou.wangcong(a)gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
net/sched/cls_api.c | 13 +++++++------
1 file changed, 7 insertions(+), 6 deletions(-)
--- a/net/sched/cls_api.c
+++ b/net/sched/cls_api.c
@@ -290,21 +290,22 @@ void tcf_block_put(struct tcf_block *blo
if (!block)
return;
- /* Hold a refcnt for all chains, except 0, so that they don't disappear
+ /* Hold a refcnt for all chains, so that they don't disappear
* while we are iterating.
*/
list_for_each_entry(chain, &block->chain_list, list)
- if (chain->index)
- tcf_chain_hold(chain);
+ tcf_chain_hold(chain);
list_for_each_entry(chain, &block->chain_list, list)
tcf_chain_flush(chain);
- /* At this point, all the chains should have refcnt >= 1. Block will be
- * freed after all chains are gone.
- */
+ /* At this point, all the chains should have refcnt >= 1. */
list_for_each_entry_safe(chain, tmp, &block->chain_list, list)
tcf_chain_put(chain);
+
+ /* Finally, put chain 0 and allow block to be freed. */
+ chain = list_first_entry(&block->chain_list, struct tcf_chain, list);
+ tcf_chain_put(chain);
}
EXPORT_SYMBOL(tcf_block_put);
Patches currently in stable-queue which might be from jiri(a)mellanox.com are
queue-4.14/net_sched-get-rid-of-rcu_barrier-in-tcf_block_put_ext.patch
queue-4.14/mlxsw-pci-wait-after-reset-before-accessing-hw.patch
queue-4.14/net-sched-crash-on-blocks-with-goto-chain-action.patch
queue-4.14/net-sched-fix-use-after-free-in-tcf_block_put_ext.patch
queue-4.14/net-sched-fix-crash-when-deleting-secondary-chains.patch
This is a note to let you know that I've just added the patch titled
net: sched: fix crash when deleting secondary chains
to the 4.14-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
net-sched-fix-crash-when-deleting-secondary-chains.patch
and it can be found in the queue-4.14 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From d7aa04a5e82b4f254d306926c81eae8df69e5200 Mon Sep 17 00:00:00 2001
From: Roman Kapl <code(a)rkapl.cz>
Date: Mon, 20 Nov 2017 22:21:13 +0100
Subject: net: sched: fix crash when deleting secondary chains
From: Roman Kapl <code(a)rkapl.cz>
commit d7aa04a5e82b4f254d306926c81eae8df69e5200 upstream.
If you flush (delete) a filter chain other than chain 0 (such as when
deleting the device), the kernel may run into a use-after-free. The
chain refcount must not be decremented unless we are sure we are done
with the chain.
To reproduce the bug, run:
ip link add dtest type dummy
tc qdisc add dev dtest ingress
tc filter add dev dtest chain 1 parent ffff: flower
ip link del dtest
Introduced in: commit f93e1cdcf42c ("net/sched: fix filter flushing"),
but unless you have KAsan or luck, you won't notice it until
commit 0dadc117ac8b ("cls_flower: use tcf_exts_get_net() before call_rcu()")
Fixes: f93e1cdcf42c ("net/sched: fix filter flushing")
Acked-by: Jiri Pirko <jiri(a)mellanox.com>
Signed-off-by: Roman Kapl <code(a)rkapl.cz>
Signed-off-by: David S. Miller <davem(a)davemloft.net>
Cc: Cong Wang <xiyou.wangcong(a)gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
net/sched/cls_api.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)
--- a/net/sched/cls_api.c
+++ b/net/sched/cls_api.c
@@ -197,14 +197,15 @@ static struct tcf_chain *tcf_chain_creat
static void tcf_chain_flush(struct tcf_chain *chain)
{
- struct tcf_proto *tp;
+ struct tcf_proto *tp = rtnl_dereference(chain->filter_chain);
if (chain->p_filter_chain)
RCU_INIT_POINTER(*chain->p_filter_chain, NULL);
- while ((tp = rtnl_dereference(chain->filter_chain)) != NULL) {
+ while (tp) {
RCU_INIT_POINTER(chain->filter_chain, tp->next);
- tcf_chain_put(chain);
tcf_proto_destroy(tp);
+ tp = rtnl_dereference(chain->filter_chain);
+ tcf_chain_put(chain);
}
}
Patches currently in stable-queue which might be from code(a)rkapl.cz are
queue-4.14/net-sched-crash-on-blocks-with-goto-chain-action.patch
queue-4.14/net-sched-fix-crash-when-deleting-secondary-chains.patch
This is a note to let you know that I've just added the patch titled
net: sched: crash on blocks with goto chain action
to the 4.14-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
net-sched-crash-on-blocks-with-goto-chain-action.patch
and it can be found in the queue-4.14 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From a60b3f515d30d0fe8537c64671926879a3548103 Mon Sep 17 00:00:00 2001
From: Roman Kapl <code(a)rkapl.cz>
Date: Fri, 24 Nov 2017 12:27:58 +0100
Subject: net: sched: crash on blocks with goto chain action
From: Roman Kapl <code(a)rkapl.cz>
commit a60b3f515d30d0fe8537c64671926879a3548103 upstream.
tcf_block_put_ext has assumed that all filters (and thus their goto
actions) are destroyed in RCU callback and thus can not race with our
list iteration. However, that is not true during netns cleanup (see
tcf_exts_get_net comment).
Prevent the user after free by holding all chains (except 0, that one is
already held). foreach_safe is not enough in this case.
To reproduce, run the following in a netns and then delete the ns:
ip link add dtest type dummy
tc qdisc add dev dtest ingress
tc filter add dev dtest chain 1 parent ffff: handle 1 prio 1 flower action goto chain 2
Fixes: 822e86d997 ("net_sched: remove tcf_block_put_deferred()")
Signed-off-by: Roman Kapl <code(a)rkapl.cz>
Acked-by: Jiri Pirko <jiri(a)mellanox.com>
Signed-off-by: David S. Miller <davem(a)davemloft.net>
Cc: Cong Wang <xiyou.wangcong(a)gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
net/sched/cls_api.c | 17 ++++++++++++-----
1 file changed, 12 insertions(+), 5 deletions(-)
--- a/net/sched/cls_api.c
+++ b/net/sched/cls_api.c
@@ -282,7 +282,8 @@ static void tcf_block_put_final(struct w
struct tcf_chain *chain, *tmp;
rtnl_lock();
- /* Only chain 0 should be still here. */
+
+ /* At this point, all the chains should have refcnt == 1. */
list_for_each_entry_safe(chain, tmp, &block->chain_list, list)
tcf_chain_put(chain);
rtnl_unlock();
@@ -290,17 +291,23 @@ static void tcf_block_put_final(struct w
}
/* XXX: Standalone actions are not allowed to jump to any chain, and bound
- * actions should be all removed after flushing. However, filters are now
- * destroyed in tc filter workqueue with RTNL lock, they can not race here.
+ * actions should be all removed after flushing.
*/
void tcf_block_put(struct tcf_block *block)
{
- struct tcf_chain *chain, *tmp;
+ struct tcf_chain *chain;
if (!block)
return;
- list_for_each_entry_safe(chain, tmp, &block->chain_list, list)
+ /* Hold a refcnt for all chains, except 0, so that they don't disappear
+ * while we are iterating.
+ */
+ list_for_each_entry(chain, &block->chain_list, list)
+ if (chain->index)
+ tcf_chain_hold(chain);
+
+ list_for_each_entry(chain, &block->chain_list, list)
tcf_chain_flush(chain);
INIT_WORK(&block->work, tcf_block_put_final);
Patches currently in stable-queue which might be from code(a)rkapl.cz are
queue-4.14/net-sched-crash-on-blocks-with-goto-chain-action.patch
queue-4.14/net-sched-fix-crash-when-deleting-secondary-chains.patch
This is a note to let you know that I've just added the patch titled
arm64: dts: marvell: mcbin: add comphy references to Ethernet ports
to the 4.14-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
arm64-dts-marvell-mcbin-add-comphy-references-to-ethernet-ports.patch
and it can be found in the queue-4.14 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From 760b3843fcd88f2a46e66eec08e2e6023a425809 Mon Sep 17 00:00:00 2001
From: Antoine Tenart <antoine.tenart(a)free-electrons.com>
Date: Thu, 21 Sep 2017 09:54:07 +0200
Subject: arm64: dts: marvell: mcbin: add comphy references to Ethernet ports
From: Antoine Tenart <antoine.tenart(a)free-electrons.com>
commit 760b3843fcd88f2a46e66eec08e2e6023a425809 upstream.
This patch adds comphy phandles to the Ethernet ports in the mcbin
device tree. The comphy is used to configure the serdes PHYs used by
these ports.
Signed-off-by: Antoine Tenart <antoine.tenart(a)free-electrons.com>
Reviewed-by: Andrew Lunn <andrew(a)lunn.ch>
Signed-off-by: Gregory CLEMENT <gregory.clement(a)free-electrons.com>
Cc: Mikulas Patocka <mpatocka(a)redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
arch/arm64/boot/dts/marvell/armada-8040-mcbin.dts | 9 +++++++++
1 file changed, 9 insertions(+)
--- a/arch/arm64/boot/dts/marvell/armada-8040-mcbin.dts
+++ b/arch/arm64/boot/dts/marvell/armada-8040-mcbin.dts
@@ -228,8 +228,11 @@
&cpm_eth0 {
status = "okay";
+ /* Network PHY */
phy = <&phy0>;
phy-mode = "10gbase-kr";
+ /* Generic PHY, providing serdes lanes */
+ phys = <&cpm_comphy4 0>;
};
&cpm_sata0 {
@@ -263,15 +266,21 @@
&cps_eth0 {
status = "okay";
+ /* Network PHY */
phy = <&phy8>;
phy-mode = "10gbase-kr";
+ /* Generic PHY, providing serdes lanes */
+ phys = <&cps_comphy4 0>;
};
&cps_eth1 {
/* CPS Lane 0 - J5 (Gigabit RJ45) */
status = "okay";
+ /* Network PHY */
phy = <&ge_phy>;
phy-mode = "sgmii";
+ /* Generic PHY, providing serdes lanes */
+ phys = <&cps_comphy0 1>;
};
&cps_pinctrl {
Patches currently in stable-queue which might be from antoine.tenart(a)free-electrons.com are
queue-4.14/arm64-dts-marvell-mcbin-add-comphy-references-to-ethernet-ports.patch
queue-4.14/crypto-inside-secure-per-request-invalidation.patch
queue-4.14/arm64-dts-marvell-add-comphy-nodes-on-cp110-master-and-slave.patch
queue-4.14/crypto-inside-secure-fix-request-allocations-in-invalidation-path.patch
queue-4.14/crypto-inside-secure-free-requests-even-if-their-handling-failed.patch
This patchset backports 4 important bug fixes for tc filter to
4.14 stable branch. Due to some big changes between 4.14 and 4.15,
the backports are not trivial, I have to adjust and fix the conflicts
manually.
Thanks to Roland for reporting the kernel warning and testing
the patches.
Reported-by: Roland Franke <fli4l(a)franke-prem.de>
Tested-by: Roland Franke <fli4l(a)franke-prem.de>
Cc: Jiri Pirko <jiri(a)mellanox.com>
Cc: Roman Kapl <code(a)rkapl.cz>
Cc: David S. Miller <davem(a)davemloft.net>
Signed-off-by: Cong Wang <xiyou.wangcong(a)gmail.com>
---
Cong Wang (1):
net_sched: get rid of rcu_barrier() in tcf_block_put_ext()
Jiri Pirko (1):
net: sched: fix use-after-free in tcf_block_put_ext
Roman Kapl (2):
net: sched: fix crash when deleting secondary chains
net: sched: crash on blocks with goto chain action
include/net/sch_generic.h | 1 -
net/sched/cls_api.c | 48 +++++++++++++++++++++++------------------------
2 files changed, 23 insertions(+), 26 deletions(-)
--
2.13.0
This is a note to let you know that I've just added the patch titled
MIPS: Implement __multi3 for GCC7 MIPS64r6 builds
to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
mips-implement-__multi3-for-gcc7-mips64r6-builds.patch
and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From ebabcf17bcd7ce968b1631ebe08236275698f39b Mon Sep 17 00:00:00 2001
From: James Hogan <jhogan(a)kernel.org>
Date: Thu, 7 Dec 2017 07:20:46 +0000
Subject: MIPS: Implement __multi3 for GCC7 MIPS64r6 builds
From: James Hogan <jhogan(a)kernel.org>
commit ebabcf17bcd7ce968b1631ebe08236275698f39b upstream.
GCC7 is a bit too eager to generate suboptimal __multi3 calls (128bit
multiply with 128bit result) for MIPS64r6 builds, even in code which
doesn't explicitly use 128bit types, such as the following:
unsigned long func(unsigned long a, unsigned long b)
{
return a > (~0UL) / b;
}
Which GCC rearanges to:
return (unsigned __int128)a * (unsigned __int128)b > 0xffffffffffffffff;
Therefore implement __multi3, but only for MIPS64r6 with GCC7 as under
normal circumstances we wouldn't expect any calls to __multi3 to be
generated from kernel code.
Reported-by: Thomas Petazzoni <thomas.petazzoni(a)free-electrons.com>
Signed-off-by: James Hogan <jhogan(a)kernel.org>
Tested-by: Waldemar Brodkorb <wbx(a)openadk.org>
Cc: Ralf Baechle <ralf(a)linux-mips.org>
Cc: Maciej W. Rozycki <macro(a)mips.com>
Cc: Matthew Fortune <matthew.fortune(a)mips.com>
Cc: Florian Fainelli <florian(a)openwrt.org>
Cc: linux-mips(a)linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17890/
Cc: Guenter Roeck <linux(a)roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
arch/mips/lib/Makefile | 3 +-
arch/mips/lib/libgcc.h | 17 +++++++++++++++
arch/mips/lib/multi3.c | 54 +++++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 73 insertions(+), 1 deletion(-)
--- a/arch/mips/lib/Makefile
+++ b/arch/mips/lib/Makefile
@@ -15,4 +15,5 @@ obj-$(CONFIG_CPU_R3000) += r3k_dump_tlb
obj-$(CONFIG_CPU_TX39XX) += r3k_dump_tlb.o
# libgcc-style stuff needed in the kernel
-obj-y += ashldi3.o ashrdi3.o bswapsi.o bswapdi.o cmpdi2.o lshrdi3.o ucmpdi2.o
+obj-y += ashldi3.o ashrdi3.o bswapsi.o bswapdi.o cmpdi2.o lshrdi3.o multi3.o \
+ ucmpdi2.o
--- a/arch/mips/lib/libgcc.h
+++ b/arch/mips/lib/libgcc.h
@@ -9,10 +9,18 @@ typedef int word_type __attribute__ ((mo
struct DWstruct {
int high, low;
};
+
+struct TWstruct {
+ long long high, low;
+};
#elif defined(__LITTLE_ENDIAN)
struct DWstruct {
int low, high;
};
+
+struct TWstruct {
+ long long low, high;
+};
#else
#error I feel sick.
#endif
@@ -22,4 +30,13 @@ typedef union {
long long ll;
} DWunion;
+#if defined(CONFIG_64BIT) && defined(CONFIG_CPU_MIPSR6)
+typedef int ti_type __attribute__((mode(TI)));
+
+typedef union {
+ struct TWstruct s;
+ ti_type ti;
+} TWunion;
+#endif
+
#endif /* __ASM_LIBGCC_H */
--- /dev/null
+++ b/arch/mips/lib/multi3.c
@@ -0,0 +1,54 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/export.h>
+
+#include "libgcc.h"
+
+/*
+ * GCC 7 suboptimally generates __multi3 calls for mips64r6, so for that
+ * specific case only we'll implement it here.
+ *
+ * See https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82981
+ */
+#if defined(CONFIG_64BIT) && defined(CONFIG_CPU_MIPSR6) && (__GNUC__ == 7)
+
+/* multiply 64-bit values, low 64-bits returned */
+static inline long long notrace dmulu(long long a, long long b)
+{
+ long long res;
+
+ asm ("dmulu %0,%1,%2" : "=r" (res) : "r" (a), "r" (b));
+ return res;
+}
+
+/* multiply 64-bit unsigned values, high 64-bits of 128-bit result returned */
+static inline long long notrace dmuhu(long long a, long long b)
+{
+ long long res;
+
+ asm ("dmuhu %0,%1,%2" : "=r" (res) : "r" (a), "r" (b));
+ return res;
+}
+
+/* multiply 128-bit values, low 128-bits returned */
+ti_type notrace __multi3(ti_type a, ti_type b)
+{
+ TWunion res, aa, bb;
+
+ aa.ti = a;
+ bb.ti = b;
+
+ /*
+ * a * b = (a.lo * b.lo)
+ * + 2^64 * (a.hi * b.lo + a.lo * b.hi)
+ * [+ 2^128 * (a.hi * b.hi)]
+ */
+ res.s.low = dmulu(aa.s.low, bb.s.low);
+ res.s.high = dmuhu(aa.s.low, bb.s.low);
+ res.s.high += dmulu(aa.s.high, bb.s.low);
+ res.s.high += dmulu(aa.s.low, bb.s.high);
+
+ return res.ti;
+}
+EXPORT_SYMBOL(__multi3);
+
+#endif /* 64BIT && CPU_MIPSR6 && GCC7 */
Patches currently in stable-queue which might be from jhogan(a)kernel.org are
queue-4.9/lib-mpi-fix-umul_ppmm-for-mips64r6.patch
queue-4.9/mips-implement-__multi3-for-gcc7-mips64r6-builds.patch
This is a note to let you know that I've just added the patch titled
MIPS: Implement __multi3 for GCC7 MIPS64r6 builds
to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
mips-implement-__multi3-for-gcc7-mips64r6-builds.patch
and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From ebabcf17bcd7ce968b1631ebe08236275698f39b Mon Sep 17 00:00:00 2001
From: James Hogan <jhogan(a)kernel.org>
Date: Thu, 7 Dec 2017 07:20:46 +0000
Subject: MIPS: Implement __multi3 for GCC7 MIPS64r6 builds
From: James Hogan <jhogan(a)kernel.org>
commit ebabcf17bcd7ce968b1631ebe08236275698f39b upstream.
GCC7 is a bit too eager to generate suboptimal __multi3 calls (128bit
multiply with 128bit result) for MIPS64r6 builds, even in code which
doesn't explicitly use 128bit types, such as the following:
unsigned long func(unsigned long a, unsigned long b)
{
return a > (~0UL) / b;
}
Which GCC rearanges to:
return (unsigned __int128)a * (unsigned __int128)b > 0xffffffffffffffff;
Therefore implement __multi3, but only for MIPS64r6 with GCC7 as under
normal circumstances we wouldn't expect any calls to __multi3 to be
generated from kernel code.
Reported-by: Thomas Petazzoni <thomas.petazzoni(a)free-electrons.com>
Signed-off-by: James Hogan <jhogan(a)kernel.org>
Tested-by: Waldemar Brodkorb <wbx(a)openadk.org>
Cc: Ralf Baechle <ralf(a)linux-mips.org>
Cc: Maciej W. Rozycki <macro(a)mips.com>
Cc: Matthew Fortune <matthew.fortune(a)mips.com>
Cc: Florian Fainelli <florian(a)openwrt.org>
Cc: linux-mips(a)linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17890/
Cc: Guenter Roeck <linux(a)roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
arch/mips/lib/Makefile | 3 +-
arch/mips/lib/libgcc.h | 17 +++++++++++++++
arch/mips/lib/multi3.c | 54 +++++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 73 insertions(+), 1 deletion(-)
--- a/arch/mips/lib/Makefile
+++ b/arch/mips/lib/Makefile
@@ -15,4 +15,5 @@ obj-$(CONFIG_CPU_R3000) += r3k_dump_tlb
obj-$(CONFIG_CPU_TX39XX) += r3k_dump_tlb.o
# libgcc-style stuff needed in the kernel
-obj-y += ashldi3.o ashrdi3.o bswapsi.o bswapdi.o cmpdi2.o lshrdi3.o ucmpdi2.o
+obj-y += ashldi3.o ashrdi3.o bswapsi.o bswapdi.o cmpdi2.o lshrdi3.o multi3.o \
+ ucmpdi2.o
--- a/arch/mips/lib/libgcc.h
+++ b/arch/mips/lib/libgcc.h
@@ -9,10 +9,18 @@ typedef int word_type __attribute__ ((mo
struct DWstruct {
int high, low;
};
+
+struct TWstruct {
+ long long high, low;
+};
#elif defined(__LITTLE_ENDIAN)
struct DWstruct {
int low, high;
};
+
+struct TWstruct {
+ long long low, high;
+};
#else
#error I feel sick.
#endif
@@ -22,4 +30,13 @@ typedef union {
long long ll;
} DWunion;
+#if defined(CONFIG_64BIT) && defined(CONFIG_CPU_MIPSR6)
+typedef int ti_type __attribute__((mode(TI)));
+
+typedef union {
+ struct TWstruct s;
+ ti_type ti;
+} TWunion;
+#endif
+
#endif /* __ASM_LIBGCC_H */
--- /dev/null
+++ b/arch/mips/lib/multi3.c
@@ -0,0 +1,54 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/export.h>
+
+#include "libgcc.h"
+
+/*
+ * GCC 7 suboptimally generates __multi3 calls for mips64r6, so for that
+ * specific case only we'll implement it here.
+ *
+ * See https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82981
+ */
+#if defined(CONFIG_64BIT) && defined(CONFIG_CPU_MIPSR6) && (__GNUC__ == 7)
+
+/* multiply 64-bit values, low 64-bits returned */
+static inline long long notrace dmulu(long long a, long long b)
+{
+ long long res;
+
+ asm ("dmulu %0,%1,%2" : "=r" (res) : "r" (a), "r" (b));
+ return res;
+}
+
+/* multiply 64-bit unsigned values, high 64-bits of 128-bit result returned */
+static inline long long notrace dmuhu(long long a, long long b)
+{
+ long long res;
+
+ asm ("dmuhu %0,%1,%2" : "=r" (res) : "r" (a), "r" (b));
+ return res;
+}
+
+/* multiply 128-bit values, low 128-bits returned */
+ti_type notrace __multi3(ti_type a, ti_type b)
+{
+ TWunion res, aa, bb;
+
+ aa.ti = a;
+ bb.ti = b;
+
+ /*
+ * a * b = (a.lo * b.lo)
+ * + 2^64 * (a.hi * b.lo + a.lo * b.hi)
+ * [+ 2^128 * (a.hi * b.hi)]
+ */
+ res.s.low = dmulu(aa.s.low, bb.s.low);
+ res.s.high = dmuhu(aa.s.low, bb.s.low);
+ res.s.high += dmulu(aa.s.high, bb.s.low);
+ res.s.high += dmulu(aa.s.low, bb.s.high);
+
+ return res.ti;
+}
+EXPORT_SYMBOL(__multi3);
+
+#endif /* 64BIT && CPU_MIPSR6 && GCC7 */
Patches currently in stable-queue which might be from jhogan(a)kernel.org are
queue-4.4/lib-mpi-fix-umul_ppmm-for-mips64r6.patch
queue-4.4/mips-implement-__multi3-for-gcc7-mips64r6-builds.patch
This is a note to let you know that I've just added the patch titled
powerpc/pseries: Enable RAS hotplug events later
to the 4.15-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
powerpc-pseries-enable-ras-hotplug-events-later.patch
and it can be found in the queue-4.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From c9dccf1d074a67d36c510845f663980d69e3409b Mon Sep 17 00:00:00 2001
From: Sam Bobroff <sam.bobroff(a)au1.ibm.com>
Date: Mon, 12 Feb 2018 11:19:29 +1100
Subject: powerpc/pseries: Enable RAS hotplug events later
From: Sam Bobroff <sam.bobroff(a)au1.ibm.com>
commit c9dccf1d074a67d36c510845f663980d69e3409b upstream.
Currently if the kernel receives a memory hot-unplug event early
enough, it may get stuck in an infinite loop in
dissolve_free_huge_pages(). This appears as a stall just after:
pseries-hotplug-mem: Attempting to hot-remove XX LMB(s) at YYYYYYYY
It appears to be caused by "minimum_order" being uninitialized, due to
init_ras_IRQ() executing before hugetlb_init().
To correct this, extract the part of init_ras_IRQ() that enables
hotplug event processing and place it in the machine_late_initcall
phase, which is guaranteed to be after hugetlb_init() is called.
Signed-off-by: Sam Bobroff <sam.bobroff(a)au1.ibm.com>
Acked-by: Balbir Singh <bsingharora(a)gmail.com>
[mpe: Reorder the functions to make the diff readable]
Signed-off-by: Michael Ellerman <mpe(a)ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
arch/powerpc/platforms/pseries/ras.c | 31 ++++++++++++++++++++++---------
1 file changed, 22 insertions(+), 9 deletions(-)
--- a/arch/powerpc/platforms/pseries/ras.c
+++ b/arch/powerpc/platforms/pseries/ras.c
@@ -49,6 +49,28 @@ static irqreturn_t ras_error_interrupt(i
/*
+ * Enable the hotplug interrupt late because processing them may touch other
+ * devices or systems (e.g. hugepages) that have not been initialized at the
+ * subsys stage.
+ */
+int __init init_ras_hotplug_IRQ(void)
+{
+ struct device_node *np;
+
+ /* Hotplug Events */
+ np = of_find_node_by_path("/event-sources/hot-plug-events");
+ if (np != NULL) {
+ if (dlpar_workqueue_init() == 0)
+ request_event_sources_irqs(np, ras_hotplug_interrupt,
+ "RAS_HOTPLUG");
+ of_node_put(np);
+ }
+
+ return 0;
+}
+machine_late_initcall(pseries, init_ras_hotplug_IRQ);
+
+/*
* Initialize handlers for the set of interrupts caused by hardware errors
* and power system events.
*/
@@ -66,15 +88,6 @@ static int __init init_ras_IRQ(void)
of_node_put(np);
}
- /* Hotplug Events */
- np = of_find_node_by_path("/event-sources/hot-plug-events");
- if (np != NULL) {
- if (dlpar_workqueue_init() == 0)
- request_event_sources_irqs(np, ras_hotplug_interrupt,
- "RAS_HOTPLUG");
- of_node_put(np);
- }
-
/* EPOW Events */
np = of_find_node_by_path("/event-sources/epow-events");
if (np != NULL) {
Patches currently in stable-queue which might be from sam.bobroff(a)au1.ibm.com are
queue-4.15/powerpc-pseries-enable-ras-hotplug-events-later.patch