* [PATCH bpf-next 2/2] bpf: add tests for direct packet access from CGROUP_SKB
From: Song Liu @ 2018-10-17 5:56 UTC (permalink / raw)
To: netdev; +Cc: ast, daniel, kernel-team, Song Liu
In-Reply-To: <20181017055606.353449-1-songliubraving@fb.com>
Tests are added to make sure CGROUP_SKB can directly access len, data,
and data_end in __sk_buff, but not other fields.
Signed-off-by: Song Liu <songliubraving@fb.com>
---
tools/testing/selftests/bpf/test_verifier.c | 30 +++++++++++++++++++++
1 file changed, 30 insertions(+)
diff --git a/tools/testing/selftests/bpf/test_verifier.c b/tools/testing/selftests/bpf/test_verifier.c
index cf4cd32b6772..aaf2ceba83dd 100644
--- a/tools/testing/selftests/bpf/test_verifier.c
+++ b/tools/testing/selftests/bpf/test_verifier.c
@@ -4862,6 +4862,36 @@ static struct bpf_test tests[] = {
.result = REJECT,
.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
},
+ {
+ "direct packet read for CGROUP_SKB",
+ .insns = {
+ BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1,
+ offsetof(struct __sk_buff, data)),
+ BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1,
+ offsetof(struct __sk_buff, data_end)),
+ BPF_LDX_MEM(BPF_W, BPF_REG_4, BPF_REG_1,
+ offsetof(struct __sk_buff, len)),
+ BPF_MOV64_REG(BPF_REG_0, BPF_REG_2),
+ BPF_ALU64_IMM(BPF_ADD, BPF_REG_0, 8),
+ BPF_JMP_REG(BPF_JGT, BPF_REG_0, BPF_REG_3, 1),
+ BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_2, 0),
+ BPF_MOV64_IMM(BPF_REG_0, 0),
+ BPF_EXIT_INSN(),
+ },
+ .result = ACCEPT,
+ .prog_type = BPF_PROG_TYPE_CGROUP_SKB,
+ },
+ {
+ "invalid access of tc_classid for CGROUP_SKB",
+ .insns = {
+ BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_1,
+ offsetof(struct __sk_buff, tc_classid)),
+ BPF_EXIT_INSN(),
+ },
+ .result = REJECT,
+ .errstr = "invalid bpf_context access",
+ .prog_type = BPF_PROG_TYPE_CGROUP_SKB,
+ },
{
"valid cgroup storage access",
.insns = {
--
2.17.1
^ permalink raw reply related
* [PATCH bpf-next 1/2] bpf: add cg_skb_is_valid_access for BPF_PROG_TYPE_CGROUP_SKB
From: Song Liu @ 2018-10-17 5:56 UTC (permalink / raw)
To: netdev; +Cc: ast, daniel, kernel-team, Song Liu
In-Reply-To: <20181017055606.353449-1-songliubraving@fb.com>
BPF programs of BPF_PROG_TYPE_CGROUP_SKB need to access headers in the
skb. This patch enables direct access of skb for these programs.
In __cgroup_bpf_run_filter_skb(), bpf_compute_data_pointers() is called
to compute proper data_end for the BPF program.
Signed-off-by: Song Liu <songliubraving@fb.com>
---
kernel/bpf/cgroup.c | 4 ++++
net/core/filter.c | 26 +++++++++++++++++++++++++-
2 files changed, 29 insertions(+), 1 deletion(-)
diff --git a/kernel/bpf/cgroup.c b/kernel/bpf/cgroup.c
index 00f6ed2e4f9a..340d496f35bd 100644
--- a/kernel/bpf/cgroup.c
+++ b/kernel/bpf/cgroup.c
@@ -566,6 +566,10 @@ int __cgroup_bpf_run_filter_skb(struct sock *sk,
save_sk = skb->sk;
skb->sk = sk;
__skb_push(skb, offset);
+
+ /* compute pointers for the bpf prog */
+ bpf_compute_data_pointers(skb);
+
ret = BPF_PROG_RUN_ARRAY(cgrp->bpf.effective[type], skb,
bpf_prog_run_save_cb);
__skb_pull(skb, offset);
diff --git a/net/core/filter.c b/net/core/filter.c
index 1a3ac6c46873..8b5a502e241f 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -5346,6 +5346,30 @@ static bool sk_filter_is_valid_access(int off, int size,
return bpf_skb_is_valid_access(off, size, type, prog, info);
}
+static bool cg_skb_is_valid_access(int off, int size,
+ enum bpf_access_type type,
+ const struct bpf_prog *prog,
+ struct bpf_insn_access_aux *info)
+{
+ if (type == BPF_WRITE)
+ return false;
+
+ switch (off) {
+ case bpf_ctx_range(struct __sk_buff, len):
+ break;
+ case bpf_ctx_range(struct __sk_buff, data):
+ info->reg_type = PTR_TO_PACKET;
+ break;
+ case bpf_ctx_range(struct __sk_buff, data_end):
+ info->reg_type = PTR_TO_PACKET_END;
+ break;
+ default:
+ return false;
+ }
+
+ return bpf_skb_is_valid_access(off, size, type, prog, info);
+}
+
static bool lwt_is_valid_access(int off, int size,
enum bpf_access_type type,
const struct bpf_prog *prog,
@@ -7038,7 +7062,7 @@ const struct bpf_prog_ops xdp_prog_ops = {
const struct bpf_verifier_ops cg_skb_verifier_ops = {
.get_func_proto = cg_skb_func_proto,
- .is_valid_access = sk_filter_is_valid_access,
+ .is_valid_access = cg_skb_is_valid_access,
.convert_ctx_access = bpf_convert_ctx_access,
};
--
2.17.1
^ permalink raw reply related
* Re: [PATCH] net-xfrm: add build time cfg option to PF_KEY SHA256 to use RFC4868-compliant truncation
From: Herbert Xu @ 2018-10-17 5:59 UTC (permalink / raw)
To: Maciej Żenczykowski; +Cc: maze, davem, steffen.klassert, netdev, lorenzo
In-Reply-To: <20181016080634.139776-1-zenczykowski@gmail.com>
Maciej Żenczykowski <zenczykowski@gmail.com> wrote:
>
> +#if IS_ENABLED(CONFIG_XFRM_HMAC_SHA256_RFC4868)
> + .icv_truncbits = 128,
> +#else
> .icv_truncbits = 96,
> +#endif
Nack. We don't want a build-time configuration knob for this.
This needs to be decided at run-time.
In fact you can already do this at run-time anyway through the
xfrm interface. So please please please just ditch whatever that
you're using that's still glued to the long-obsolete (more than a
decade) af_key interface and switch it over to xfrm.
Thanks,
--
Email: Herbert Xu <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt
^ permalink raw reply
* Re: [PATCH] net-xfrm: add build time cfg option to PF_KEY SHA256 to use RFC4868-compliant truncation
From: Maciej Żenczykowski @ 2018-10-17 6:01 UTC (permalink / raw)
To: Herbert Xu
Cc: David S. Miller, steffen.klassert, Linux NetDev, Lorenzo Colitti
In-Reply-To: <20181017055950.m3wpucoyobt43k44@gondor.apana.org.au>
I'm afraid it's nothing we're using. It's what people are using.
I guess we'll just carry this patch for a few more years.
^ permalink raw reply
* Re: [PATCH 0/4] Add SOCFPGA System Manager
From: Thor Thayer @ 2018-10-17 13:59 UTC (permalink / raw)
To: lee.jones, peppe.cavallaro, dinguyen, linux, alexandre.torgue,
joabreu
Cc: davem, mchehab+samsung, catalin.marinas, akpm, arnd, aisheng.dong,
linux-kernel, netdev, linux-arm-kernel
In-Reply-To: <021aaa02-1138-e538-3d02-ff639541d0f3@linux.intel.com>
Gentle ping again...
Any comments on this patch series?
On 10/10/2018 09:42 AM, Thor Thayer wrote:
> Hi
> On 09/24/2018 05:09 PM, thor.thayer@linux.intel.com wrote:
>> From: Thor Thayer <thor.thayer@linux.intel.com>
>>
>> Add MFD driver for ARM64 SOCFPGA System Manager to steer
>> System Manager calls appropriately.
>> The SOCFPGA System Manager includes registers from several
>> SOC peripherals.
>>
>> On ARM32, syscon handles this aggregated register grouping.
>> Redirect System Manager calls to syscon for ARM32 SOCFPGA
>> systems.
>>
>> The ARM64 System Manager can only be accessed from priority
>> level EL3 so this new MFD driver handles the calls to EL3.
>>
>> Thor Thayer (4):
>> mfd: altera-sysmgr: Add SOCFPGA System Manager abstraction
>> ARM: socfpga_defconfig: Enable CONFIG_MTD_ALTERA_SYSMGR
>> arm64: defconfig: Enable CONFIG_MTD_ALTERA_SYSMGR
>> net: stmmac: socfpga: Convert to shared System Manager driver
>>
>> MAINTAINERS | 6 +
>> arch/arm/configs/socfpga_defconfig | 1 +
>> arch/arm64/configs/defconfig | 1 +
>> drivers/mfd/Kconfig | 9 +
>> drivers/mfd/Makefile | 1 +
>> drivers/mfd/altera-sysmgr.c | 310
>> +++++++++++++++++++++
>> .../net/ethernet/stmicro/stmmac/dwmac-socfpga.c | 4 +-
>> include/linux/mfd/altera-sysmgr.h | 113 ++++++++
>> 8 files changed, 444 insertions(+), 1 deletion(-)
>> create mode 100644 drivers/mfd/altera-sysmgr.c
>> create mode 100644 include/linux/mfd/altera-sysmgr.h
>>
> Gentle ping.
>
> Thor
^ permalink raw reply
* Re: [PATCH v2 1/1] crypto:chelsio: Update ntx queue received from cxgb4
From: Herbert Xu @ 2018-10-17 6:22 UTC (permalink / raw)
To: Harsh Jain
Cc: atul.gupta, indranil, swise, varun, ganeshgr, netdev,
linux-crypto, LinoSanfilippo
In-Reply-To: <c9489de40840ee72e9fcc9c5b3e8008592e8dc6d.1539418425.git.harsh@chelsio.com>
On Sat, Oct 13, 2018 at 01:46:56PM +0530, Harsh Jain wrote:
> Update cxgb4 to send No. of Tx Queue created in lldinfo struct
> and use the same ntxq in chcr driver.
>
> This patch depends on following commit
> commit add92a817e60e308a419693413a38d9d1e663aff
> "Fix memory corruption in DMA Mapped buffers"
>
> v2:
> Free txq_info in error case as pointed by Lino Sanfilippo.
>
> Signed-off-by: Harsh Jain <harsh@chelsio.com>
Patch applied. Thanks.
--
Email: Herbert Xu <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt
^ permalink raw reply
* Re: [PATCH bpf-next 2/3] bpf: emit RECORD_MMAP events for bpf prog load/unload
From: Song Liu @ 2018-10-17 6:43 UTC (permalink / raw)
To: David Ahern
Cc: Alexei Starovoitov, acme, Peter Zijlstra, Alexei Starovoitov,
David S . Miller, Daniel Borkmann, Networking, kernel-team
In-Reply-To: <1593d595-58ef-22b3-d721-859453425e26@gmail.com>
Hi David,
On Tue, Oct 16, 2018 at 4:43 PM David Ahern <dsahern@gmail.com> wrote:
>
> On 10/15/18 4:33 PM, Song Liu wrote:
> > I am working with Alexei on the idea of fetching BPF program information via
> > BPF_OBJ_GET_INFO_BY_FD cmd. I added PERF_RECORD_BPF_EVENT
> > to perf_event_type, and dumped these events to perf event ring buffer.
> >
> > I found that perf will not process event until the end of perf-record:
> >
> > root@virt-test:~# ~/perf record -ag -- sleep 10
> > ...... 10 seconds later
> > [ perf record: Woken up 34 times to write data ]
> > machine__process_bpf_event: prog_id 6 loaded
> > machine__process_bpf_event: prog_id 6 unloaded
> > [ perf record: Captured and wrote 9.337 MB perf.data (93178 samples) ]
> >
> > In this example, the bpf program was loaded and then unloaded in
> > another terminal. When machine__process_bpf_event() processes
> > the load event, the bpf program is already unloaded. Therefore,
> > machine__process_bpf_event() will not be able to get information
> > about the program via BPF_OBJ_GET_INFO_BY_FD cmd.
> >
> > To solve this problem, we will need to run BPF_OBJ_GET_INFO_BY_FD
> > as soon as perf get the event from kernel. I looked around the perf
> > code for a while. But I haven't found a good example where some
> > events are processed before the end of perf-record. Could you
> > please help me with this?
>
> perf record does not process events as they are generated. Its sole job
> is pushing data from the maps to a file as fast as possible meaning in
> bulk based on current read and write locations.
>
> Adding code to process events will add significant overhead to the
> record command and will not really solve your race problem.
Thanks for the comment.
I agree that processing events while recording has significant overhead.
In this case, perf user space need to know details about the the jited BPF
program. It is impossible to pass all these details to user space through
the relatively stable ring_buffer API. Therefore, some processing of the
data is necessary (get bpf prog_id from ring buffer, and then fetch program
details via BPF_OBJ_GET_INFO_BY_FD.
I have some idea on processing important data with relatively low overhead.
Let me try implement it.
Thanks again,
Song
^ permalink raw reply
* Re: [RFC] virtio_net: add local_bh_disable() around u64_stats_update_begin
From: Jason Wang @ 2018-10-17 6:48 UTC (permalink / raw)
To: Toshiaki Makita, Sebastian Andrzej Siewior, netdev,
virtualization
Cc: tglx, Michael S. Tsirkin, David S. Miller
In-Reply-To: <68582c17-27bf-43f4-cbe5-96ec712a704c@lab.ntt.co.jp>
On 2018/10/17 上午9:13, Toshiaki Makita wrote:
> On 2018/10/17 1:55, Sebastian Andrzej Siewior wrote:
>> on 32bit, lockdep notices:
>> | ================================
>> | WARNING: inconsistent lock state
>> | 4.19.0-rc8+ #9 Tainted: G W
>> | --------------------------------
>> | inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage.
>> | ip/1106 [HC0[0]:SC1[1]:HE1:SE0] takes:
>> | (ptrval) (&syncp->seq#2){+.?.}, at: net_rx_action+0xc8/0x380
>> | {SOFTIRQ-ON-W} state was registered at:
>> | lock_acquire+0x7e/0x170
>> | try_fill_recv+0x5fa/0x700
>> | virtnet_open+0xe0/0x180
>> | __dev_open+0xae/0x130
>> | __dev_change_flags+0x17f/0x200
>> | dev_change_flags+0x23/0x60
>> | do_setlink+0x2bb/0xa20
>> | rtnl_newlink+0x523/0x830
>> | rtnetlink_rcv_msg+0x14b/0x470
>> | netlink_rcv_skb+0x6e/0xf0
>> | rtnetlink_rcv+0xd/0x10
>> | netlink_unicast+0x16e/0x1f0
>> | netlink_sendmsg+0x1af/0x3a0
>> | ___sys_sendmsg+0x20f/0x240
>> | __sys_sendmsg+0x39/0x80
>> | sys_socketcall+0x13a/0x2a0
>> | do_int80_syscall_32+0x50/0x180
>> | restore_all+0x0/0xb2
>> | irq event stamp: 3326
>> | hardirqs last enabled at (3326): [<c159e6d0>] net_rx_action+0x80/0x380
>> | hardirqs last disabled at (3325): [<c159e6aa>] net_rx_action+0x5a/0x380
>> | softirqs last enabled at (3322): [<c14b440d>] virtnet_napi_enable+0xd/0x60
>> | softirqs last disabled at (3323): [<c101d63d>] call_on_stack+0xd/0x50
>> |
>> | other info that might help us debug this:
>> | Possible unsafe locking scenario:
>> |
>> | CPU0
>> | ----
>> | lock(&syncp->seq#2);
>> | <Interrupt>
>> | lock(&syncp->seq#2);
>> |
>> | *** DEADLOCK ***
> IIUC try_fill_recv is called only when NAPI is disabled from process
> context, so there should be no point to race with virtnet_receive which
> is called from NAPI handler.
>
> I'm not sure what condition triggered this warning.
>
>
> Toshiaki Makita
Or maybe NAPI is enabled unexpectedly somewhere?
Btw, the schedule_delayed_work() in virtnet_open() is also suspicious,
if the work is executed before virtnet_napi_enable(), there will be a
deadloop for napi_disable().
Thanks
>
>
>> This is the "up" path which is not a hotpath. There is also
>> refill_work().
>> It might be unwise to add the local_bh_disable() to try_fill_recv()
>> because if it is used mostly in BH so that local_bh_en+dis might be a
>> waste of cycles.
>>
>> Adding local_bh_disable() around try_fill_recv() for the non-BH call
>> sites would render GFP_KERNEL pointless.
>>
>> Also, ptr->var++ is not an atomic operation even on 64bit CPUs. Which
>> means if try_fill_recv() runs on CPU0 (via virtnet_receive()) then the
>> worker might run on CPU1.
>>
>> Do we care or is this just stupid stats? Any suggestions?
>>
>> This warning appears since commit 461f03dc99cf6 ("virtio_net: Add kick stats").
>>
>> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
>> ---
>> drivers/net/virtio_net.c | 2 ++
>> 1 file changed, 2 insertions(+)
>>
>> diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
>> index dab504ec5e502..d782160cfa882 100644
>> --- a/drivers/net/virtio_net.c
>> +++ b/drivers/net/virtio_net.c
>> @@ -1206,9 +1206,11 @@ static bool try_fill_recv(struct virtnet_info *vi, struct receive_queue *rq,
>> break;
>> } while (rq->vq->num_free);
>> if (virtqueue_kick_prepare(rq->vq) && virtqueue_notify(rq->vq)) {
>> + local_bh_disable();
>> u64_stats_update_begin(&rq->stats.syncp);
>> rq->stats.kicks++;
>> u64_stats_update_end(&rq->stats.syncp);
>> + local_bh_enable();
>> }
>>
>> return !oom;
>>
^ permalink raw reply
* Re: [PATCH v3] virtio_net: avoid using netif_tx_disable() for serializing tx routine
From: Michael S. Tsirkin @ 2018-10-17 15:09 UTC (permalink / raw)
To: Ake Koomsin
Cc: Jason Wang, David S. Miller, virtualization, netdev, linux-kernel
In-Reply-To: <20181017104419.13003-1-ake@igel.co.jp>
On Wed, Oct 17, 2018 at 07:44:12PM +0900, Ake Koomsin wrote:
> Commit 713a98d90c5e ("virtio-net: serialize tx routine during reset")
> introduces netif_tx_disable() after netif_device_detach() in order to
> avoid use-after-free of tx queues. However, there are two issues.
>
> 1) Its operation is redundant with netif_device_detach() in case the
> interface is running.
> 2) In case of the interface is not running before suspending and
> resuming, the tx does not get resumed by netif_device_attach().
> This results in losing network connectivity.
>
> It is better to use netif_tx_lock_bh()/netif_tx_unlock_bh() instead for
> serializing tx routine during reset. This also preserves the symmetry
> of netif_device_detach() and netif_device_attach().
>
> Fixes commit 713a98d90c5e ("virtio-net: serialize tx routine during reset")
> Signed-off-by: Ake Koomsin <ake@igel.co.jp>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Thanks a lot for debugging!
Seems like stable material to me, right?
> ---
> drivers/net/virtio_net.c | 5 ++++-
> 1 file changed, 4 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
> index 3f5aa59c37b7..3e2c041d76ac 100644
> --- a/drivers/net/virtio_net.c
> +++ b/drivers/net/virtio_net.c
> @@ -2267,8 +2267,9 @@ static void virtnet_freeze_down(struct virtio_device *vdev)
> /* Make sure no work handler is accessing the device */
> flush_work(&vi->config_work);
>
> + netif_tx_lock_bh(vi->dev);
> netif_device_detach(vi->dev);
> - netif_tx_disable(vi->dev);
> + netif_tx_unlock_bh(vi->dev);
> cancel_delayed_work_sync(&vi->refill);
>
> if (netif_running(vi->dev)) {
> @@ -2304,7 +2305,9 @@ static int virtnet_restore_up(struct virtio_device *vdev)
> }
> }
>
> + netif_tx_lock_bh(vi->dev);
> netif_device_attach(vi->dev);
> + netif_tx_unlock_bh(vi->dev);
> return err;
> }
>
> --
> 2.19.1
^ permalink raw reply
* [PATCH bpf-next v2 03/13] tools/bpf: sync kernel btf.h header
From: Yonghong Song @ 2018-10-17 7:23 UTC (permalink / raw)
To: ast, kafai, daniel, netdev; +Cc: kernel-team
In-Reply-To: <20181017072315.2766920-1-yhs@fb.com>
The kernel uapi btf.h is synced to the tools directory.
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Yonghong Song <yhs@fb.com>
---
tools/include/uapi/linux/btf.h | 9 ++++++---
1 file changed, 6 insertions(+), 3 deletions(-)
diff --git a/tools/include/uapi/linux/btf.h b/tools/include/uapi/linux/btf.h
index 972265f32871..63f8500e6f34 100644
--- a/tools/include/uapi/linux/btf.h
+++ b/tools/include/uapi/linux/btf.h
@@ -40,7 +40,8 @@ struct btf_type {
/* "size" is used by INT, ENUM, STRUCT and UNION.
* "size" tells the size of the type it is describing.
*
- * "type" is used by PTR, TYPEDEF, VOLATILE, CONST and RESTRICT.
+ * "type" is used by PTR, TYPEDEF, VOLATILE, CONST, RESTRICT,
+ * FUNC and FUNC_PROTO.
* "type" is a type_id referring to another type.
*/
union {
@@ -64,8 +65,10 @@ struct btf_type {
#define BTF_KIND_VOLATILE 9 /* Volatile */
#define BTF_KIND_CONST 10 /* Const */
#define BTF_KIND_RESTRICT 11 /* Restrict */
-#define BTF_KIND_MAX 11
-#define NR_BTF_KINDS 12
+#define BTF_KIND_FUNC 12 /* Function */
+#define BTF_KIND_FUNC_PROTO 13 /* Function Prototype */
+#define BTF_KIND_MAX 13
+#define NR_BTF_KINDS 14
/* For some specific BTF_KIND, "struct btf_type" is immediately
* followed by extra data.
--
2.17.1
^ permalink raw reply related
* [PATCH bpf-next v2 01/13] bpf: btf: Break up btf_type_is_void()
From: Yonghong Song @ 2018-10-17 7:23 UTC (permalink / raw)
To: ast, kafai, daniel, netdev; +Cc: kernel-team
In-Reply-To: <20181017072315.2766920-1-yhs@fb.com>
This patch breaks up btf_type_is_void() into
btf_type_is_void() and btf_type_is_fwd().
It also adds btf_type_nosize() to better describe it is
testing a type has nosize info.
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Yonghong Song <yhs@fb.com>
---
kernel/bpf/btf.c | 37 ++++++++++++++++++++++---------------
1 file changed, 22 insertions(+), 15 deletions(-)
diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c
index 378cef70341c..be406d8906ce 100644
--- a/kernel/bpf/btf.c
+++ b/kernel/bpf/btf.c
@@ -306,15 +306,22 @@ static bool btf_type_is_modifier(const struct btf_type *t)
static bool btf_type_is_void(const struct btf_type *t)
{
- /* void => no type and size info.
- * Hence, FWD is also treated as void.
- */
- return t == &btf_void || BTF_INFO_KIND(t->info) == BTF_KIND_FWD;
+ return t == &btf_void;
+}
+
+static bool btf_type_is_fwd(const struct btf_type *t)
+{
+ return BTF_INFO_KIND(t->info) == BTF_KIND_FWD;
+}
+
+static bool btf_type_nosize(const struct btf_type *t)
+{
+ return btf_type_is_void(t) || btf_type_is_fwd(t);
}
-static bool btf_type_is_void_or_null(const struct btf_type *t)
+static bool btf_type_nosize_or_null(const struct btf_type *t)
{
- return !t || btf_type_is_void(t);
+ return !t || btf_type_nosize(t);
}
/* union is only a special case of struct:
@@ -826,7 +833,7 @@ const struct btf_type *btf_type_id_size(const struct btf *btf,
u32 size = 0;
size_type = btf_type_by_id(btf, size_type_id);
- if (btf_type_is_void_or_null(size_type))
+ if (btf_type_nosize_or_null(size_type))
return NULL;
if (btf_type_has_size(size_type)) {
@@ -842,7 +849,7 @@ const struct btf_type *btf_type_id_size(const struct btf *btf,
size = btf->resolved_sizes[size_type_id];
size_type_id = btf->resolved_ids[size_type_id];
size_type = btf_type_by_id(btf, size_type_id);
- if (btf_type_is_void(size_type))
+ if (btf_type_nosize_or_null(size_type))
return NULL;
}
@@ -1164,7 +1171,7 @@ static int btf_modifier_resolve(struct btf_verifier_env *env,
}
/* "typedef void new_void", "const void"...etc */
- if (btf_type_is_void(next_type))
+ if (btf_type_is_void(next_type) || btf_type_is_fwd(next_type))
goto resolved;
if (!env_type_is_resolve_sink(env, next_type) &&
@@ -1178,7 +1185,7 @@ static int btf_modifier_resolve(struct btf_verifier_env *env,
* pretty print).
*/
if (!btf_type_id_size(btf, &next_type_id, &next_type_size) &&
- !btf_type_is_void(btf_type_id_resolve(btf, &next_type_id))) {
+ !btf_type_nosize(btf_type_id_resolve(btf, &next_type_id))) {
btf_verifier_log_type(env, v->t, "Invalid type_id");
return -EINVAL;
}
@@ -1205,7 +1212,7 @@ static int btf_ptr_resolve(struct btf_verifier_env *env,
}
/* "void *" */
- if (btf_type_is_void(next_type))
+ if (btf_type_is_void(next_type) || btf_type_is_fwd(next_type))
goto resolved;
if (!env_type_is_resolve_sink(env, next_type) &&
@@ -1235,7 +1242,7 @@ static int btf_ptr_resolve(struct btf_verifier_env *env,
}
if (!btf_type_id_size(btf, &next_type_id, &next_type_size) &&
- !btf_type_is_void(btf_type_id_resolve(btf, &next_type_id))) {
+ !btf_type_nosize(btf_type_id_resolve(btf, &next_type_id))) {
btf_verifier_log_type(env, v->t, "Invalid type_id");
return -EINVAL;
}
@@ -1396,7 +1403,7 @@ static int btf_array_resolve(struct btf_verifier_env *env,
/* Check array->index_type */
index_type_id = array->index_type;
index_type = btf_type_by_id(btf, index_type_id);
- if (btf_type_is_void_or_null(index_type)) {
+ if (btf_type_nosize_or_null(index_type)) {
btf_verifier_log_type(env, v->t, "Invalid index");
return -EINVAL;
}
@@ -1415,7 +1422,7 @@ static int btf_array_resolve(struct btf_verifier_env *env,
/* Check array->type */
elem_type_id = array->type;
elem_type = btf_type_by_id(btf, elem_type_id);
- if (btf_type_is_void_or_null(elem_type)) {
+ if (btf_type_nosize_or_null(elem_type)) {
btf_verifier_log_type(env, v->t,
"Invalid elem");
return -EINVAL;
@@ -1615,7 +1622,7 @@ static int btf_struct_resolve(struct btf_verifier_env *env,
const struct btf_type *member_type = btf_type_by_id(env->btf,
member_type_id);
- if (btf_type_is_void_or_null(member_type)) {
+ if (btf_type_nosize_or_null(member_type)) {
btf_verifier_log_member(env, v->t, member,
"Invalid member");
return -EINVAL;
--
2.17.1
^ permalink raw reply related
* [PATCH bpf-next v2 02/13] bpf: btf: Add BTF_KIND_FUNC and BTF_KIND_FUNC_PROTO
From: Yonghong Song @ 2018-10-17 7:23 UTC (permalink / raw)
To: ast, kafai, daniel, netdev; +Cc: kernel-team
In-Reply-To: <20181017072315.2766920-1-yhs@fb.com>
This patch adds BTF_KIND_FUNC and BTF_KIND_FUNC_PROTO
support to the type section. BTF_KIND_FUNC_PROTO is used
to specify the type of a function pointer. With this,
BTF has a complete set of C types (except float).
BTF_KIND_FUNC is used to specify the signature of a
defined subprogram. BTF_KIND_FUNC_PROTO can be referenced
by another type, e.g., a pointer type, and BTF_KIND_FUNC
type cannot be referenced by another type.
For both BTF_KIND_FUNC and BTF_KIND_FUNC_PROTO types,
the func return type is in t->type (where t is a
"struct btf_type" object). The func args are an array of
u32s immediately following object "t".
As a concrete example, for the C program below,
$ cat test.c
int foo(int (*bar)(int)) { return bar(5); }
with LLVM patch https://reviews.llvm.org/D53261
in Debug mode, we have
$ clang -target bpf -g -O2 -mllvm -debug-only=btf -c test.c
Type Table:
[1] FUNC NameOff=1 Info=0x0c000001 Size/Type=2
ParamType=3
[2] INT NameOff=11 Info=0x01000000 Size/Type=4
Desc=0x01000020
[3] PTR NameOff=0 Info=0x02000000 Size/Type=4
[4] FUNC_PROTO NameOff=0 Info=0x0d000001 Size/Type=2
ParamType=2
String Table:
0 :
1 : foo
5 : .text
11 : int
15 : test.c
22 : int foo(int (*bar)(int)) { return bar(5); }
FuncInfo Table:
SecNameOff=5
InsnOffset=<Omitted> TypeId=1
...
(Eventually we shall have bpftool to dump btf information
like the above.)
Function "foo" has a FUNC type (type_id = 1).
The parameter of "foo" has type_id 3 which is PTR->FUNC_PROTO,
where FUNC_PROTO refers to function pointer "bar".
In FuncInfo Table, for section .text, the function,
with to-be-determined offset (marked as <Omitted>),
has type_id=1 which refers to a FUNC type.
This way, the function signature is
available to both kernel and user space.
Here, the insn offset is not available during the dump time
as relocation is resolved pretty late in the compilation process.
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Yonghong Song <yhs@fb.com>
---
include/uapi/linux/btf.h | 9 +-
kernel/bpf/btf.c | 280 ++++++++++++++++++++++++++++++++++-----
2 files changed, 253 insertions(+), 36 deletions(-)
diff --git a/include/uapi/linux/btf.h b/include/uapi/linux/btf.h
index 972265f32871..63f8500e6f34 100644
--- a/include/uapi/linux/btf.h
+++ b/include/uapi/linux/btf.h
@@ -40,7 +40,8 @@ struct btf_type {
/* "size" is used by INT, ENUM, STRUCT and UNION.
* "size" tells the size of the type it is describing.
*
- * "type" is used by PTR, TYPEDEF, VOLATILE, CONST and RESTRICT.
+ * "type" is used by PTR, TYPEDEF, VOLATILE, CONST, RESTRICT,
+ * FUNC and FUNC_PROTO.
* "type" is a type_id referring to another type.
*/
union {
@@ -64,8 +65,10 @@ struct btf_type {
#define BTF_KIND_VOLATILE 9 /* Volatile */
#define BTF_KIND_CONST 10 /* Const */
#define BTF_KIND_RESTRICT 11 /* Restrict */
-#define BTF_KIND_MAX 11
-#define NR_BTF_KINDS 12
+#define BTF_KIND_FUNC 12 /* Function */
+#define BTF_KIND_FUNC_PROTO 13 /* Function Prototype */
+#define BTF_KIND_MAX 13
+#define NR_BTF_KINDS 14
/* For some specific BTF_KIND, "struct btf_type" is immediately
* followed by extra data.
diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c
index be406d8906ce..763f8e06bc91 100644
--- a/kernel/bpf/btf.c
+++ b/kernel/bpf/btf.c
@@ -5,6 +5,7 @@
#include <uapi/linux/types.h>
#include <linux/seq_file.h>
#include <linux/compiler.h>
+#include <linux/ctype.h>
#include <linux/errno.h>
#include <linux/slab.h>
#include <linux/anon_inodes.h>
@@ -259,6 +260,8 @@ static const char * const btf_kind_str[NR_BTF_KINDS] = {
[BTF_KIND_VOLATILE] = "VOLATILE",
[BTF_KIND_CONST] = "CONST",
[BTF_KIND_RESTRICT] = "RESTRICT",
+ [BTF_KIND_FUNC] = "FUNC",
+ [BTF_KIND_FUNC_PROTO] = "FUNC_PROTO",
};
struct btf_kind_operations {
@@ -281,6 +284,9 @@ struct btf_kind_operations {
static const struct btf_kind_operations * const kind_ops[NR_BTF_KINDS];
static struct btf_type btf_void;
+static int btf_resolve(struct btf_verifier_env *env,
+ const struct btf_type *t, u32 type_id);
+
static bool btf_type_is_modifier(const struct btf_type *t)
{
/* Some of them is not strictly a C modifier
@@ -314,9 +320,20 @@ static bool btf_type_is_fwd(const struct btf_type *t)
return BTF_INFO_KIND(t->info) == BTF_KIND_FWD;
}
+static bool btf_type_is_func(const struct btf_type *t)
+{
+ return BTF_INFO_KIND(t->info) == BTF_KIND_FUNC;
+}
+
+static bool btf_type_is_func_proto(const struct btf_type *t)
+{
+ return BTF_INFO_KIND(t->info) == BTF_KIND_FUNC_PROTO;
+}
+
static bool btf_type_nosize(const struct btf_type *t)
{
- return btf_type_is_void(t) || btf_type_is_fwd(t);
+ return btf_type_is_void(t) || btf_type_is_fwd(t) ||
+ btf_type_is_func(t) || btf_type_is_func_proto(t);
}
static bool btf_type_nosize_or_null(const struct btf_type *t)
@@ -433,6 +450,27 @@ static bool btf_name_offset_valid(const struct btf *btf, u32 offset)
offset < btf->hdr.str_len;
}
+static bool btf_name_valid_identifier(const struct btf *btf, u32 offset)
+{
+ /* offset must be valid */
+ const char *src = &btf->strings[offset];
+ const char *src_limit;
+
+ if (!isalpha(*src) && *src != '_')
+ return false;
+
+ /* set a limit on identifier length */
+ src_limit = src + KSYM_NAME_LEN;
+ src++;
+ while (*src && src < src_limit) {
+ if (!isalnum(*src) && *src != '_')
+ return false;
+ src++;
+ }
+
+ return !*src;
+}
+
static const char *btf_name_by_offset(const struct btf *btf, u32 offset)
{
if (!offset)
@@ -747,7 +785,9 @@ static bool env_type_is_resolve_sink(const struct btf_verifier_env *env,
/* int, enum or void is a sink */
return !btf_type_needs_resolve(next_type);
case RESOLVE_PTR:
- /* int, enum, void, struct or array is a sink for ptr */
+ /* int, enum, void, struct, array or func_ptoto is a sink
+ * for ptr
+ */
return !btf_type_is_modifier(next_type) &&
!btf_type_is_ptr(next_type);
case RESOLVE_STRUCT_OR_ARRAY:
@@ -1170,6 +1210,14 @@ static int btf_modifier_resolve(struct btf_verifier_env *env,
return -EINVAL;
}
+ if (btf_type_is_func_proto(next_type)) {
+ if (env->resolve_mode == RESOLVE_PTR)
+ goto resolved;
+
+ btf_verifier_log_type(env, v->t, "Invalid type_id");
+ return -EINVAL;
+ }
+
/* "typedef void new_void", "const void"...etc */
if (btf_type_is_void(next_type) || btf_type_is_fwd(next_type))
goto resolved;
@@ -1185,7 +1233,8 @@ static int btf_modifier_resolve(struct btf_verifier_env *env,
* pretty print).
*/
if (!btf_type_id_size(btf, &next_type_id, &next_type_size) &&
- !btf_type_nosize(btf_type_id_resolve(btf, &next_type_id))) {
+ (!btf_type_nosize(btf_type_id_resolve(btf, &next_type_id)) ||
+ btf_type_is_func(next_type))) {
btf_verifier_log_type(env, v->t, "Invalid type_id");
return -EINVAL;
}
@@ -1212,7 +1261,8 @@ static int btf_ptr_resolve(struct btf_verifier_env *env,
}
/* "void *" */
- if (btf_type_is_void(next_type) || btf_type_is_fwd(next_type))
+ if (btf_type_is_void(next_type) || btf_type_is_fwd(next_type) ||
+ btf_type_is_func_proto(next_type))
goto resolved;
if (!env_type_is_resolve_sink(env, next_type) &&
@@ -1242,7 +1292,8 @@ static int btf_ptr_resolve(struct btf_verifier_env *env,
}
if (!btf_type_id_size(btf, &next_type_id, &next_type_size) &&
- !btf_type_nosize(btf_type_id_resolve(btf, &next_type_id))) {
+ (!btf_type_nosize(btf_type_id_resolve(btf, &next_type_id)) ||
+ btf_type_is_func(next_type))) {
btf_verifier_log_type(env, v->t, "Invalid type_id");
return -EINVAL;
}
@@ -1550,6 +1601,14 @@ static s32 btf_struct_check_meta(struct btf_verifier_env *env,
return -EINVAL;
}
+ if (member->name_off &&
+ !btf_name_valid_identifier(btf, member->name_off)) {
+ btf_verifier_log_member(env, t, member,
+ "Invalid member name:%s",
+ btf_name_by_offset(btf, member->name_off));
+ return -EINVAL;
+ }
+
/* A member cannot be in type void */
if (!member->type || !BTF_TYPE_ID_VALID(member->type)) {
btf_verifier_log_member(env, t, member,
@@ -1787,6 +1846,142 @@ static struct btf_kind_operations enum_ops = {
.seq_show = btf_enum_seq_show,
};
+static s32 btf_func_check_meta(struct btf_verifier_env *env,
+ const struct btf_type *t,
+ u32 meta_left)
+{
+ u32 meta_needed = btf_type_vlen(t) * sizeof(u32);
+
+ if (meta_left < meta_needed) {
+ btf_verifier_log_basic(env, t,
+ "meta_left:%u meta_needed:%u",
+ meta_left, meta_needed);
+ return -EINVAL;
+ }
+
+ btf_verifier_log_type(env, t, NULL);
+
+ return meta_needed;
+}
+
+static void btf_func_log(struct btf_verifier_env *env,
+ const struct btf_type *t)
+{
+ u16 nr_args = btf_type_vlen(t), i;
+ u32 *args = (u32 *)(t + 1);
+
+ btf_verifier_log(env, "return=%u args=(", t->type);
+ if (!nr_args) {
+ btf_verifier_log(env, "void");
+ goto done;
+ }
+
+ if (nr_args == 1 && !args[0]) {
+ /* Only one vararg */
+ btf_verifier_log(env, "vararg");
+ goto done;
+ }
+
+ btf_verifier_log(env, "%u", args[0]);
+ for (i = 1; i < nr_args - 1; i++)
+ btf_verifier_log(env, ", %u", args[i]);
+ if (nr_args > 1) {
+ u32 last_arg = args[nr_args - 1];
+
+ if (last_arg)
+ btf_verifier_log(env, ", %u", last_arg);
+ else
+ btf_verifier_log(env, ", vararg");
+ }
+
+done:
+ btf_verifier_log(env, ")");
+}
+
+static int btf_func_check(struct btf_verifier_env *env,
+ const struct btf_type *t,
+ u32 type_id)
+{
+ u16 nr_args = btf_type_vlen(t), i;
+ const struct btf *btf = env->btf;
+ const struct btf_type *ret_type;
+ u32 *args = (u32 *)(t + 1);
+ u32 ret_type_id;
+ int err;
+
+ /* Check func return type which could be "void" (t->type == 0) */
+ ret_type_id = t->type;
+ if (ret_type_id) {
+ /* return type is not "void" */
+ ret_type = btf_type_by_id(btf, ret_type_id);
+ if (btf_type_needs_resolve(ret_type) &&
+ !env_type_is_resolved(env, ret_type_id)) {
+ err = btf_resolve(env, ret_type, ret_type_id);
+ if (err)
+ return err;
+ }
+
+ /* Ensure the return type is a type that has a size */
+ if (!btf_type_id_size(btf, &ret_type_id, NULL)) {
+ btf_verifier_log_type(env, t, "Invalid return type");
+ return -EINVAL;
+ }
+ }
+
+ if (!nr_args)
+ return 0;
+
+ /* Last func arg type_id could be 0 if it is a vararg */
+ if (!args[nr_args - 1])
+ nr_args--;
+
+ err = 0;
+ for (i = 0; i < nr_args; i++) {
+ const struct btf_type *arg_type;
+ u32 arg_type_id;
+
+ arg_type_id = args[i];
+ arg_type = btf_type_by_id(btf, arg_type_id);
+ if (!arg_type) {
+ btf_verifier_log_type(env, t, "Invalid arg#%u", i + 1);
+ err = -EINVAL;
+ break;
+ }
+
+ if (btf_type_needs_resolve(arg_type) &&
+ !env_type_is_resolved(env, arg_type_id)) {
+ err = btf_resolve(env, arg_type, arg_type_id);
+ if (err)
+ break;
+ }
+
+ if (!btf_type_id_size(btf, &arg_type_id, NULL)) {
+ btf_verifier_log_type(env, t, "Invalid arg#%u", i + 1);
+ err = -EINVAL;
+ break;
+ }
+ }
+
+ return err;
+}
+
+static struct btf_kind_operations func_ops = {
+ .check_meta = btf_func_check_meta,
+ .resolve = btf_df_resolve,
+ /*
+ * BPF_KIND_FUNC_PROTO cannot be directly referred by
+ * a struct's member.
+ *
+ * It should be a funciton pointer instead.
+ * (i.e. struct's member -> BTF_KIND_PTR -> BTF_KIND_FUNC_PROTO)
+ *
+ * Hence, there is no btf_func_check_member().
+ */
+ .check_member = btf_df_check_member,
+ .log_details = btf_func_log,
+ .seq_show = btf_df_seq_show,
+};
+
static const struct btf_kind_operations * const kind_ops[NR_BTF_KINDS] = {
[BTF_KIND_INT] = &int_ops,
[BTF_KIND_PTR] = &ptr_ops,
@@ -1799,6 +1994,8 @@ static const struct btf_kind_operations * const kind_ops[NR_BTF_KINDS] = {
[BTF_KIND_VOLATILE] = &modifier_ops,
[BTF_KIND_CONST] = &modifier_ops,
[BTF_KIND_RESTRICT] = &modifier_ops,
+ [BTF_KIND_FUNC] = &func_ops,
+ [BTF_KIND_FUNC_PROTO] = &func_ops,
};
static s32 btf_check_meta(struct btf_verifier_env *env,
@@ -1870,30 +2067,6 @@ static int btf_check_all_metas(struct btf_verifier_env *env)
return 0;
}
-static int btf_resolve(struct btf_verifier_env *env,
- const struct btf_type *t, u32 type_id)
-{
- const struct resolve_vertex *v;
- int err = 0;
-
- env->resolve_mode = RESOLVE_TBD;
- env_stack_push(env, t, type_id);
- while (!err && (v = env_stack_peak(env))) {
- env->log_type_id = v->type_id;
- err = btf_type_ops(v->t)->resolve(env, v);
- }
-
- env->log_type_id = type_id;
- if (err == -E2BIG)
- btf_verifier_log_type(env, t,
- "Exceeded max resolving depth:%u",
- MAX_RESOLVE_DEPTH);
- else if (err == -EEXIST)
- btf_verifier_log_type(env, t, "Loop detected");
-
- return err;
-}
-
static bool btf_resolve_valid(struct btf_verifier_env *env,
const struct btf_type *t,
u32 type_id)
@@ -1927,6 +2100,39 @@ static bool btf_resolve_valid(struct btf_verifier_env *env,
return false;
}
+static int btf_resolve(struct btf_verifier_env *env,
+ const struct btf_type *t, u32 type_id)
+{
+ u32 save_log_type_id = env->log_type_id;
+ const struct resolve_vertex *v;
+ int err = 0;
+
+ env->resolve_mode = RESOLVE_TBD;
+ env_stack_push(env, t, type_id);
+ while (!err && (v = env_stack_peak(env))) {
+ env->log_type_id = v->type_id;
+ err = btf_type_ops(v->t)->resolve(env, v);
+ }
+
+ env->log_type_id = type_id;
+ if (err == -E2BIG) {
+ btf_verifier_log_type(env, t,
+ "Exceeded max resolving depth:%u",
+ MAX_RESOLVE_DEPTH);
+ } else if (err == -EEXIST) {
+ btf_verifier_log_type(env, t, "Loop detected");
+ }
+
+ /* Final sanity check */
+ if (!err && !btf_resolve_valid(env, t, type_id)) {
+ btf_verifier_log_type(env, t, "Invalid resolve state");
+ err = -EINVAL;
+ }
+
+ env->log_type_id = save_log_type_id;
+ return err;
+}
+
static int btf_check_all_types(struct btf_verifier_env *env)
{
struct btf *btf = env->btf;
@@ -1949,10 +2155,18 @@ static int btf_check_all_types(struct btf_verifier_env *env)
return err;
}
- if (btf_type_needs_resolve(t) &&
- !btf_resolve_valid(env, t, type_id)) {
- btf_verifier_log_type(env, t, "Invalid resolve state");
- return -EINVAL;
+ if (btf_type_is_func(t) || btf_type_is_func_proto(t)) {
+ if (btf_type_is_func(t) &&
+ (!btf_name_offset_valid(btf, t->name_off) ||
+ !btf_name_valid_identifier(btf, t->name_off))) {
+ btf_verifier_log_type(env, t,
+ "Invalid type_id");
+ return -EINVAL;
+ }
+
+ err = btf_func_check(env, t, type_id);
+ if (err)
+ return err;
}
}
--
2.17.1
^ permalink raw reply related
* [PATCH bpf-next v2 00/13] bpf: add btf func info support
From: Yonghong Song @ 2018-10-17 7:23 UTC (permalink / raw)
To: ast, kafai, daniel, netdev; +Cc: kernel-team
The BTF support was added to kernel by Commit 69b693f0aefa
("bpf: btf: Introduce BPF Type Format (BTF)"), which introduced
.BTF section into ELF file and is primarily
used for map pretty print.
pahole is used to convert dwarf to BTF for ELF files.
This patch added func info support to the kernel so we can
get better ksym's for bpf function calls. Basically,
pairs of bpf function calls and their corresponding types
are passed to the kernel. Extracting function names from
the types, the kernel is able to construct a ksym for
each function call with embedded function name.
LLVM patch https://reviews.llvm.org/D53261
can generate func info, encoded in .BTF.ext ELF section.
In addition, it also added support for FUNC and FUNC_PROTO
types, which are also supported through this patch set.
The following is an example to show FUNC and
FUNC_PROTO difference, compiled with the above LLVM patch
with Debug mode.
-bash-4.2$ cat test.c
int foo(int (*bar)(int)) { return bar(5); }
-bash-4.2$ clang -target bpf -g -O2 -mllvm -debug-only=btf -c test.c
Type Table:
[1] FUNC name_off=1 info=0x0c000001 size/type=2
param_type=3
[2] INT name_off=11 info=0x01000000 size/type=4
desc=0x01000020
[3] PTR name_off=0 info=0x02000000 size/type=4
[4] FUNC_PROTO name_off=0 info=0x0d000001 size/type=2
param_type=2
String Table:
0 :
1 : foo
5 : .text
11 : int
15 : test.c
22 : int foo(int (*bar)(int)) { return bar(5); }
FuncInfo Table:
sec_name_off=5
insn_offset=<Omitted> type_id=1
...
In the above, type and string tables are in .BTF section and
the func info in .BTF.ext. The "<Omitted>" is the
insn offset which is not available during the dump time but
resolved during later compilation process.
Following the format specification at Patch #9 and examine the
raw data in .BTF.ext section, we have
FuncInfo Table:
sec_name_off=5
insn_offset=0 type_id=1
The (insn_offset, type_id) can be passed to the kernel
so the kernel can find the func name and use it in the ksym.
Below is a demonstration from Patch #13.
$ bpftool prog dump jited id 1
int _dummy_tracepoint(struct dummy_tracepoint_args * ):
bpf_prog_b07ccb89267cf242__dummy_tracepoint:
0: push %rbp
1: mov %rsp,%rbp
......
3c: add $0x28,%rbp
40: leaveq
41: retq
int test_long_fname_1(struct dummy_tracepoint_args * ):
bpf_prog_2dcecc18072623fc_test_long_fname_1:
0: push %rbp
1: mov %rsp,%rbp
......
3a: add $0x28,%rbp
3e: leaveq
3f: retq
int test_long_fname_2(struct dummy_tracepoint_args * ):
bpf_prog_89d64e4abf0f0126_test_long_fname_2:
0: push %rbp
1: mov %rsp,%rbp
......
80: add $0x28,%rbp
84: leaveq
85: retq
For the patchset,
Patch #1 refactors the code to break up btf_type_is_void().
Patch #2 introduces new BTF types BTF_KIND_FUNC and BTF_KIND_FUNC_PROTO.
Patch #3 syncs btf.h header to tools directory.
Patch #4 adds btf func/func_proto self tests in test_btf.
Patch #5 adds kernel interface to load func_info to kernel
and pass func_info to userspace.
Patch #6 syncs bpf.h header to tools directory.
Patch #7 adds news btf/func_info related fields in libbpf
program load function.
Patch #8 extends selftest test_btf to test load/retrieve func_type info.
Patch #9 adds .BTF.ext func info support.
Patch #10 changes Makefile to avoid using pahole if llvm is capable of
generating BTF sections.
Patch #11 refactors to have btf_get_from_id() in libbpf for reuse.
Patch #12 enhance test_btf file testing to test func info.
Patch #13 adds bpftool support for func signature dump.
Yonghong Song (13):
bpf: btf: Break up btf_type_is_void()
bpf: btf: Add BTF_KIND_FUNC and BTF_KIND_FUNC_PROTO
tools/bpf: sync kernel btf.h header
tools/bpf: add btf func/func_proto unit tests in selftest test_btf
bpf: get better bpf_prog ksyms based on btf func type_id
tools/bpf: sync kernel uapi bpf.h header to tools directory
tools/bpf: add new fields for program load in lib/bpf
tools/bpf: extends test_btf to test load/retrieve func_type info
tools/bpf: add support to read .BTF.ext sections
tools/bpf: do not use pahole if clang/llvm can generate BTF sections
tools/bpf: refactor to implement btf_get_from_id() in lib/bpf
tools/bpf: enhance test_btf file testing to test func info
tools/bpf: bpftool: add support for jited func types
Changelogs:
v1 -> v2:
. Added missing sign-off
. Limited the func_name/struct_member_name length for validity test
. Removed/changed several verifier messages
. Modified several commit messages to remove line_off reference
include/linux/bpf.h | 2 +
include/linux/bpf_verifier.h | 1 +
include/linux/btf.h | 2 +
include/uapi/linux/bpf.h | 11 +
include/uapi/linux/btf.h | 9 +-
kernel/bpf/btf.c | 325 +++++++++--
kernel/bpf/core.c | 10 +
kernel/bpf/syscall.c | 83 ++-
kernel/bpf/verifier.c | 46 ++
samples/bpf/Makefile | 8 +
tools/bpf/bpftool/btf_dumper.c | 96 ++++
tools/bpf/bpftool/main.h | 2 +
tools/bpf/bpftool/map.c | 68 +--
tools/bpf/bpftool/prog.c | 54 ++
tools/include/uapi/linux/bpf.h | 11 +
tools/include/uapi/linux/btf.h | 9 +-
tools/lib/bpf/bpf.c | 3 +
tools/lib/bpf/bpf.h | 3 +
tools/lib/bpf/btf.c | 305 ++++++++++
tools/lib/bpf/btf.h | 33 ++
tools/lib/bpf/libbpf.c | 53 +-
tools/testing/selftests/bpf/Makefile | 8 +
tools/testing/selftests/bpf/test_btf.c | 566 ++++++++++++++++++-
tools/testing/selftests/bpf/test_btf_haskv.c | 16 +-
tools/testing/selftests/bpf/test_btf_nokv.c | 16 +-
25 files changed, 1611 insertions(+), 129 deletions(-)
--
2.17.1
^ permalink raw reply
* [PATCH bpf-next v2 04/13] tools/bpf: add btf func/func_proto unit tests in selftest test_btf
From: Yonghong Song @ 2018-10-17 7:23 UTC (permalink / raw)
To: ast, kafai, daniel, netdev; +Cc: kernel-team
In-Reply-To: <20181017072315.2766920-1-yhs@fb.com>
Add several BTF_KIND_FUNC and BTF_KIND_FUNC_PROTO
unit tests in bpf selftest test_btf.
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Yonghong Song <yhs@fb.com>
---
tools/lib/bpf/btf.c | 4 +
tools/testing/selftests/bpf/test_btf.c | 216 +++++++++++++++++++++++++
2 files changed, 220 insertions(+)
diff --git a/tools/lib/bpf/btf.c b/tools/lib/bpf/btf.c
index 449591aa9900..33095fc1860b 100644
--- a/tools/lib/bpf/btf.c
+++ b/tools/lib/bpf/btf.c
@@ -165,6 +165,10 @@ static int btf_parse_type_sec(struct btf *btf, btf_print_fn_t err_log)
case BTF_KIND_ENUM:
next_type += vlen * sizeof(struct btf_enum);
break;
+ case BTF_KIND_FUNC:
+ case BTF_KIND_FUNC_PROTO:
+ next_type += vlen * sizeof(int);
+ break;
case BTF_KIND_TYPEDEF:
case BTF_KIND_PTR:
case BTF_KIND_FWD:
diff --git a/tools/testing/selftests/bpf/test_btf.c b/tools/testing/selftests/bpf/test_btf.c
index f42b3396d622..b6461c3c5e11 100644
--- a/tools/testing/selftests/bpf/test_btf.c
+++ b/tools/testing/selftests/bpf/test_btf.c
@@ -1374,6 +1374,222 @@ static struct btf_raw_test raw_tests[] = {
.map_create_err = true,
},
+{
+ .descr = "func pointer #1",
+ .raw_types = {
+ BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4), /* [1] */
+ BTF_TYPE_INT_ENC(0, 0, 0, 32, 4), /* [2] */
+ /* int (*func)(int, unsigned int) */
+ BTF_TYPE_ENC(0, BTF_INFO_ENC(BTF_KIND_FUNC_PROTO, 0, 2), 1), /* [3] */
+ 1, 2,
+ BTF_TYPE_ENC(0, BTF_INFO_ENC(BTF_KIND_PTR, 0, 0), 3), /* [4] */
+ BTF_END_RAW,
+ },
+ .str_sec = "",
+ .str_sec_size = sizeof(""),
+ .map_type = BPF_MAP_TYPE_ARRAY,
+ .map_name = "func_type_check_btf",
+ .key_size = sizeof(int),
+ .value_size = sizeof(int),
+ .key_type_id = 1,
+ .value_type_id = 1,
+ .max_entries = 4,
+},
+
+{
+ .descr = "func pointer #2",
+ .raw_types = {
+ BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4), /* [1] */
+ BTF_TYPE_INT_ENC(0, 0, 0, 32, 4), /* [2] */
+ /* void (*func)(int, unsigned int, ....) */
+ BTF_TYPE_ENC(0, BTF_INFO_ENC(BTF_KIND_FUNC_PROTO, 0, 3), 0), /* [3] */
+ 1, 2, 0,
+ BTF_TYPE_ENC(0, BTF_INFO_ENC(BTF_KIND_PTR, 0, 0), 3), /* [4] */
+ BTF_END_RAW,
+ },
+ .str_sec = "",
+ .str_sec_size = sizeof(""),
+ .map_type = BPF_MAP_TYPE_ARRAY,
+ .map_name = "func_type_check_btf",
+ .key_size = sizeof(int),
+ .value_size = sizeof(int),
+ .key_type_id = 1,
+ .value_type_id = 1,
+ .max_entries = 4,
+},
+
+{
+ .descr = "func pointer #3",
+ .raw_types = {
+ BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4), /* [1] */
+ BTF_TYPE_INT_ENC(0, 0, 0, 32, 4), /* [2] */
+ /* void (*func)(void, int, unsigned int) */
+ BTF_TYPE_ENC(0, BTF_INFO_ENC(BTF_KIND_FUNC_PROTO, 0, 3), 0), /* [3] */
+ 1, 0, 2,
+ BTF_TYPE_ENC(0, BTF_INFO_ENC(BTF_KIND_PTR, 0, 0), 3), /* [4] */
+ BTF_END_RAW,
+ },
+ .str_sec = "",
+ .str_sec_size = sizeof(""),
+ .map_type = BPF_MAP_TYPE_ARRAY,
+ .map_name = "func_type_check_btf",
+ .key_size = sizeof(int),
+ .value_size = sizeof(int),
+ .key_type_id = 1,
+ .value_type_id = 1,
+ .max_entries = 4,
+ .btf_load_err = true,
+ .err_str = "Invalid arg#2",
+},
+
+{
+ .descr = "func pointer #4",
+ .raw_types = {
+ BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4), /* [1] */
+ BTF_TYPE_INT_ENC(0, 0, 0, 32, 4), /* [2] */
+ /*
+ * Testing:
+ * BTF_KIND_CONST => BTF_KIND_TYPEDEF => BTF_KIND_PTR =>
+ * BTF_KIND_FUNC_PROTO
+ */
+ /* typedef void (*func_ptr)(int, unsigned int) */
+ BTF_TYPE_ENC(0, BTF_INFO_ENC(BTF_KIND_TYPEDEF, 0, 0), 5),/* [3] */
+ /* const func_ptr */
+ BTF_TYPE_ENC(0, BTF_INFO_ENC(BTF_KIND_CONST, 0, 0), 3), /* [4] */
+ BTF_TYPE_ENC(0, BTF_INFO_ENC(BTF_KIND_PTR, 0, 0), 6), /* [5] */
+ BTF_TYPE_ENC(0, BTF_INFO_ENC(BTF_KIND_FUNC_PROTO, 0, 2), 0), /* [6] */
+ 1, 2,
+ BTF_END_RAW,
+ },
+ .str_sec = "",
+ .str_sec_size = sizeof(""),
+ .map_type = BPF_MAP_TYPE_ARRAY,
+ .map_name = "func_type_check_btf",
+ .key_size = sizeof(int),
+ .value_size = sizeof(int),
+ .key_type_id = 1,
+ .value_type_id = 1,
+ .max_entries = 4,
+},
+
+{
+ .descr = "func pointer #5",
+ .raw_types = {
+ BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4), /* [1] */
+ BTF_TYPE_INT_ENC(0, 0, 0, 32, 4), /* [2] */
+ /*
+ * Skipped the BTF_KIND_PTR.
+ * BTF_KIND_CONST => BTF_KIND_TYPEDEF => BTF_KIND_FUNC_PROTO
+ */
+ BTF_TYPE_ENC(0, BTF_INFO_ENC(BTF_KIND_CONST, 0, 0), 4), /* [3] */
+ BTF_TYPE_ENC(0, BTF_INFO_ENC(BTF_KIND_TYPEDEF, 0, 0), 5),/* [4] */
+ BTF_TYPE_ENC(0, BTF_INFO_ENC(BTF_KIND_FUNC_PROTO, 0, 2), 0), /* [5] */
+ 1, 2,
+ BTF_END_RAW,
+ },
+ .str_sec = "",
+ .str_sec_size = sizeof(""),
+ .map_type = BPF_MAP_TYPE_ARRAY,
+ .map_name = "func_type_check_btf",
+ .key_size = sizeof(int),
+ .value_size = sizeof(int),
+ .key_type_id = 1,
+ .value_type_id = 1,
+ .max_entries = 4,
+ .btf_load_err = true,
+ .err_str = "Invalid type_id",
+},
+
+{
+ /* Test btf_resolve() in btf_check_func() */
+ .descr = "func pointer #6",
+ .raw_types = {
+ BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4), /* [1] */
+ /* void (*func)(const void *) */
+ BTF_TYPE_ENC(0, BTF_INFO_ENC(BTF_KIND_FUNC_PROTO, 0, 1), 0), /* [2] */
+ 4,
+ BTF_TYPE_ENC(0, BTF_INFO_ENC(BTF_KIND_PTR, 0, 0), 2), /* [3] */
+ BTF_TYPE_ENC(0, BTF_INFO_ENC(BTF_KIND_CONST, 0, 0), 5), /* [4] */
+ BTF_TYPE_ENC(0, BTF_INFO_ENC(BTF_KIND_PTR, 0, 0), 0), /* [5] */
+ BTF_END_RAW,
+ },
+ .str_sec = "",
+ .str_sec_size = sizeof(""),
+ .map_type = BPF_MAP_TYPE_ARRAY,
+ .map_name = "func_type_check_btf",
+ .key_size = sizeof(int),
+ .value_size = sizeof(int),
+ .key_type_id = 1,
+ .value_type_id = 1,
+ .max_entries = 4,
+},
+
+{
+ .descr = "func #1",
+ .raw_types = {
+ BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4), /* [1] */
+ BTF_TYPE_INT_ENC(0, 0, 0, 32, 4), /* [2] */
+ BTF_TYPE_ENC(NAME_TBD, BTF_INFO_ENC(BTF_KIND_FUNC, 0, 2), 1), /* [3] */
+ 1, 2,
+ BTF_END_RAW,
+ },
+ .str_sec = "\0A\0",
+ .str_sec_size = sizeof("\0A\0"),
+ .map_type = BPF_MAP_TYPE_ARRAY,
+ .map_name = "func_type_check_btf",
+ .key_size = sizeof(int),
+ .value_size = sizeof(int),
+ .key_type_id = 1,
+ .value_type_id = 1,
+ .max_entries = 4,
+},
+
+{
+ .descr = "func #2",
+ .raw_types = {
+ BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4), /* [1] */
+ BTF_TYPE_INT_ENC(0, 0, 0, 32, 4), /* [2] */
+ BTF_TYPE_ENC(NAME_TBD, BTF_INFO_ENC(BTF_KIND_FUNC, 0, 2), 1), /* [3] */
+ 1, 2,
+ BTF_TYPE_ENC(0, BTF_INFO_ENC(BTF_KIND_PTR, 0, 0), 3), /* [4] */
+ BTF_END_RAW,
+ },
+ .str_sec = "\0A\0",
+ .str_sec_size = sizeof("\0A\0"),
+ .map_type = BPF_MAP_TYPE_ARRAY,
+ .map_name = "func_type_check_btf",
+ .key_size = sizeof(int),
+ .value_size = sizeof(int),
+ .key_type_id = 1,
+ .value_type_id = 1,
+ .max_entries = 4,
+ .btf_load_err = true,
+ .err_str = "Invalid type_id",
+},
+
+{
+ .descr = "func #3",
+ .raw_types = {
+ BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4), /* [1] */
+ BTF_TYPE_INT_ENC(0, 0, 0, 32, 4), /* [2] */
+ BTF_TYPE_ENC(0, BTF_INFO_ENC(BTF_KIND_TYPEDEF, 0, 0), 4),/* [3] */
+ BTF_TYPE_ENC(NAME_TBD, BTF_INFO_ENC(BTF_KIND_FUNC, 0, 2), 0), /* [4] */
+ 1, 2,
+ BTF_END_RAW,
+ },
+ .str_sec = "\0A\0",
+ .str_sec_size = sizeof("\0A\0"),
+ .map_type = BPF_MAP_TYPE_ARRAY,
+ .map_name = "func_type_check_btf",
+ .key_size = sizeof(int),
+ .value_size = sizeof(int),
+ .key_type_id = 1,
+ .value_type_id = 1,
+ .max_entries = 4,
+ .btf_load_err = true,
+ .err_str = "Invalid type_id",
+},
+
}; /* struct btf_raw_test raw_tests[] */
static const char *get_next_str(const char *start, const char *end)
--
2.17.1
^ permalink raw reply related
* [PATCH bpf-next v2 08/13] tools/bpf: extends test_btf to test load/retrieve func_type info
From: Yonghong Song @ 2018-10-17 7:23 UTC (permalink / raw)
To: ast, kafai, daniel, netdev; +Cc: kernel-team
In-Reply-To: <20181017072344.2767700-1-yhs@fb.com>
A two function bpf program is loaded with btf and func_info.
After successful prog load, the bpf_get_info syscall is called
to retrieve prog info to ensure the types returned from the
kernel matches the types passed to the kernel from the
user space.
Several negative tests are also added to test loading/retriving
of func_type info.
Signed-off-by: Yonghong Song <yhs@fb.com>
---
tools/testing/selftests/bpf/test_btf.c | 278 ++++++++++++++++++++++++-
1 file changed, 275 insertions(+), 3 deletions(-)
diff --git a/tools/testing/selftests/bpf/test_btf.c b/tools/testing/selftests/bpf/test_btf.c
index b6461c3c5e11..e03a8cea4bb7 100644
--- a/tools/testing/selftests/bpf/test_btf.c
+++ b/tools/testing/selftests/bpf/test_btf.c
@@ -5,6 +5,7 @@
#include <linux/btf.h>
#include <linux/err.h>
#include <linux/kernel.h>
+#include <linux/filter.h>
#include <bpf/bpf.h>
#include <sys/resource.h>
#include <libelf.h>
@@ -22,9 +23,13 @@
#include "bpf_rlimit.h"
#include "bpf_util.h"
+#define MAX_INSNS 512
+#define MAX_SUBPROGS 16
+
static uint32_t pass_cnt;
static uint32_t error_cnt;
static uint32_t skip_cnt;
+static bool jit_enabled;
#define CHECK(condition, format...) ({ \
int __ret = !!(condition); \
@@ -60,6 +65,24 @@ static int __base_pr(const char *format, ...)
return err;
}
+static bool is_jit_enabled(void)
+{
+ const char *jit_sysctl = "/proc/sys/net/core/bpf_jit_enable";
+ bool enabled = false;
+ int sysctl_fd;
+
+ sysctl_fd = open(jit_sysctl, 0, O_RDONLY);
+ if (sysctl_fd != -1) {
+ char tmpc;
+
+ if (read(sysctl_fd, &tmpc, sizeof(tmpc)) == 1)
+ enabled = (tmpc != '0');
+ close(sysctl_fd);
+ }
+
+ return enabled;
+}
+
#define BTF_INFO_ENC(kind, root, vlen) \
((!!(root) << 31) | ((kind) << 24) | ((vlen) & BTF_MAX_VLEN))
@@ -103,6 +126,7 @@ static struct args {
bool get_info_test;
bool pprint_test;
bool always_log;
+ bool func_type_test;
} args;
static char btf_log_buf[BTF_LOG_BUF_SIZE];
@@ -2693,16 +2717,256 @@ static int test_pprint(void)
return err;
}
+static struct btf_func_type_test {
+ const char *descr;
+ const char *str_sec;
+ __u32 raw_types[MAX_NR_RAW_TYPES];
+ __u32 str_sec_size;
+ struct bpf_insn insns[MAX_INSNS];
+ __u32 prog_type;
+ struct bpf_func_info func_info[MAX_SUBPROGS];
+ __u32 func_info_len;
+ bool expected_prog_load_failure;
+} func_type_test[] = {
+
+{
+ .descr = "func_type test #1",
+ .str_sec = "\0int\0unsigned int\0funcA\0funcB",
+ .raw_types = {
+ BTF_TYPE_INT_ENC(NAME_TBD, BTF_INT_SIGNED, 0, 32, 4), /* [1] */
+ BTF_TYPE_INT_ENC(NAME_TBD, 0, 0, 32, 4), /* [2] */
+ BTF_TYPE_ENC(NAME_TBD, BTF_INFO_ENC(BTF_KIND_FUNC, 0, 2), 1), /* [3] */
+ 1, 2,
+ BTF_TYPE_ENC(NAME_TBD, BTF_INFO_ENC(BTF_KIND_FUNC, 0, 2), 1), /* [4] */
+ 2, 1,
+ BTF_END_RAW,
+ },
+ .str_sec_size = sizeof("\0int\0unsigned int\0funcA\0funcB"),
+ .insns = {
+ BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 1, 0, 2),
+ BPF_MOV64_IMM(BPF_REG_0, 1),
+ BPF_EXIT_INSN(),
+ BPF_MOV64_IMM(BPF_REG_0, 2),
+ BPF_EXIT_INSN(),
+ },
+ .prog_type = BPF_PROG_TYPE_TRACEPOINT,
+ .func_info = { {0, 3}, {3, 4} },
+ .func_info_len = 2 * sizeof(struct bpf_func_info),
+},
+
+{
+ .descr = "func_type test #2",
+ .str_sec = "\0int\0unsigned int\0funcA\0funcB",
+ .raw_types = {
+ BTF_TYPE_INT_ENC(NAME_TBD, BTF_INT_SIGNED, 0, 32, 4), /* [1] */
+ BTF_TYPE_INT_ENC(NAME_TBD, 0, 0, 32, 4), /* [2] */
+ /* incorrect func type */
+ BTF_TYPE_ENC(NAME_TBD, BTF_INFO_ENC(BTF_KIND_FUNC_PROTO, 0, 2), 1), /* [3] */
+ 1, 2,
+ BTF_TYPE_ENC(NAME_TBD, BTF_INFO_ENC(BTF_KIND_FUNC, 0, 2), 1), /* [4] */
+ 2, 1,
+ BTF_END_RAW,
+ },
+ .str_sec_size = sizeof("\0int\0unsigned int\0funcA\0funcB"),
+ .insns = {
+ BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 1, 0, 2),
+ BPF_MOV64_IMM(BPF_REG_0, 1),
+ BPF_EXIT_INSN(),
+ BPF_MOV64_IMM(BPF_REG_0, 2),
+ BPF_EXIT_INSN(),
+ },
+ .prog_type = BPF_PROG_TYPE_TRACEPOINT,
+ .func_info = { {0, 3}, {3, 4} },
+ .func_info_len = 2 * sizeof(struct bpf_func_info),
+ .expected_prog_load_failure = true,
+},
+
+{
+ .descr = "func_type test #3",
+ .str_sec = "\0int\0unsigned int\0funcA\0funcB",
+ .raw_types = {
+ BTF_TYPE_INT_ENC(NAME_TBD, BTF_INT_SIGNED, 0, 32, 4), /* [1] */
+ BTF_TYPE_INT_ENC(NAME_TBD, 0, 0, 32, 4), /* [2] */
+ BTF_TYPE_ENC(NAME_TBD, BTF_INFO_ENC(BTF_KIND_FUNC, 0, 2), 1), /* [3] */
+ 1, 2,
+ BTF_TYPE_ENC(NAME_TBD, BTF_INFO_ENC(BTF_KIND_FUNC, 0, 2), 1), /* [4] */
+ 2, 1,
+ BTF_END_RAW,
+ },
+ .str_sec_size = sizeof("\0int\0unsigned int\0funcA\0funcB"),
+ .insns = {
+ BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 1, 0, 2),
+ BPF_MOV64_IMM(BPF_REG_0, 1),
+ BPF_EXIT_INSN(),
+ BPF_MOV64_IMM(BPF_REG_0, 2),
+ BPF_EXIT_INSN(),
+ },
+ .prog_type = BPF_PROG_TYPE_TRACEPOINT,
+ .func_info = { {0, 3}, {3, 4} },
+ /* incorrect func_info_len */
+ .func_info_len = sizeof(struct bpf_func_info),
+ .expected_prog_load_failure = true,
+},
+
+{
+ .descr = "func_type test #4",
+ .str_sec = "\0int\0unsigned int\0funcA\0funcB",
+ .raw_types = {
+ BTF_TYPE_INT_ENC(NAME_TBD, BTF_INT_SIGNED, 0, 32, 4), /* [1] */
+ BTF_TYPE_INT_ENC(NAME_TBD, 0, 0, 32, 4), /* [2] */
+ BTF_TYPE_ENC(NAME_TBD, BTF_INFO_ENC(BTF_KIND_FUNC, 0, 2), 1), /* [3] */
+ 1, 2,
+ BTF_TYPE_ENC(NAME_TBD, BTF_INFO_ENC(BTF_KIND_FUNC, 0, 2), 1), /* [4] */
+ 2, 1,
+ BTF_END_RAW,
+ },
+ .str_sec_size = sizeof("\0int\0unsigned int\0funcA\0funcB"),
+ .insns = {
+ BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 1, 0, 2),
+ BPF_MOV64_IMM(BPF_REG_0, 1),
+ BPF_EXIT_INSN(),
+ BPF_MOV64_IMM(BPF_REG_0, 2),
+ BPF_EXIT_INSN(),
+ },
+ .prog_type = BPF_PROG_TYPE_TRACEPOINT,
+ /* incorrect func_info insn_offset */
+ .func_info = { {0, 3}, {2, 4} },
+ .func_info_len = 2 * sizeof(struct bpf_func_info),
+ .expected_prog_load_failure = true,
+},
+
+};
+
+static size_t probe_prog_length(const struct bpf_insn *fp)
+{
+ size_t len;
+
+ for (len = MAX_INSNS - 1; len > 0; --len)
+ if (fp[len].code != 0 || fp[len].imm != 0)
+ break;
+ return len + 1;
+}
+
+static int do_test_func_type(int test_num)
+{
+ const struct btf_func_type_test *test = &func_type_test[test_num];
+ __u32 func_lens[4], func_types[4], info_len;
+ struct bpf_load_program_attr attr = {};
+ unsigned int raw_btf_size;
+ struct bpf_prog_info info = {};
+ int btf_fd, prog_fd, err = 0;
+ void *raw_btf;
+
+ fprintf(stderr, "%s......", test->descr);
+ raw_btf = btf_raw_create(&hdr_tmpl, test->raw_types,
+ test->str_sec, test->str_sec_size,
+ &raw_btf_size);
+
+ if (!raw_btf)
+ return -1;
+
+ *btf_log_buf = '\0';
+ btf_fd = bpf_load_btf(raw_btf, raw_btf_size,
+ btf_log_buf, BTF_LOG_BUF_SIZE,
+ args.always_log);
+ free(raw_btf);
+
+ if (CHECK(btf_fd == -1, "invalid btf_fd errno:%d", errno)) {
+ fprintf(stderr, "%s\n", btf_log_buf);
+ err = -1;
+ goto done;
+ }
+
+ attr.prog_type = test->prog_type;
+ attr.insns = test->insns;
+ attr.insns_cnt = probe_prog_length(attr.insns);
+ attr.license = "GPL";
+ attr.prog_btf_fd = btf_fd;
+ attr.func_info_len = test->func_info_len;
+ attr.func_info = test->func_info;
+
+ *btf_log_buf = '\0';
+ prog_fd = bpf_load_program_xattr(&attr, btf_log_buf,
+ BTF_LOG_BUF_SIZE);
+ if (test->expected_prog_load_failure && prog_fd == -1) {
+ err = 0;
+ goto done;
+ }
+ if (CHECK(prog_fd == -1, "invalid prog_id errno:%d", errno)) {
+ fprintf(stderr, "%s\n", btf_log_buf);
+ err = -1;
+ goto done;
+ }
+ if (!jit_enabled) {
+ skip_cnt++;
+ fprintf(stderr, "SKIPPED, please enable sysctl bpf_jit_enable\n");
+ err = 0;
+ goto done;
+ }
+
+ info_len = sizeof(struct bpf_prog_info);
+ info.nr_jited_func_types = 4;
+ info.nr_jited_func_lens = 4;
+ info.jited_func_types = ptr_to_u64(&func_types[0]);
+ info.jited_func_lens = ptr_to_u64(&func_lens[0]);
+ err = bpf_obj_get_info_by_fd(prog_fd, &info, &info_len);
+ if (CHECK(err == -1, "invalid get info errno:%d", errno)) {
+ fprintf(stderr, "%s\n", btf_log_buf);
+ err = -1;
+ goto done;
+ }
+ if (CHECK(info.nr_jited_func_lens != 2,
+ "incorrect info.nr_jited_func_lens %d\n",
+ info.nr_jited_func_lens)) {
+ err = -1;
+ goto done;
+ }
+ if (CHECK(info.nr_jited_func_types != 2,
+ "incorrect info.nr_jited_func_types %d\n",
+ info.nr_jited_func_types)) {
+ err = -1;
+ goto done;
+ }
+ if (CHECK(info.btf_id == 0, "incorrect btf_id = 0")) {
+ err = -1;
+ goto done;
+ }
+ if (CHECK(func_types[0] != test->func_info[0].type_id ||
+ func_types[1] != test->func_info[1].type_id,
+ "incorrect func_types (%u, %u) expected (%u %d)",
+ func_types[0], func_types[1],
+ test->func_info[0].type_id, test->func_info[1].type_id)) {
+ err = -1;
+ goto done;
+ }
+
+done:
+ return err;
+}
+
+static int test_func_type(void)
+{
+ unsigned int i;
+ int err = 0;
+
+ for (i = 0; i < ARRAY_SIZE(func_type_test); i++)
+ err |= count_result(do_test_func_type(i));
+
+ return err;
+}
+
static void usage(const char *cmd)
{
- fprintf(stderr, "Usage: %s [-l] [[-r test_num (1 - %zu)] | [-g test_num (1 - %zu)] | [-f test_num (1 - %zu)] | [-p]]\n",
+ fprintf(stderr, "Usage: %s [-l] [[-r test_num (1 - %zu)] |"
+ " [-g test_num (1 - %zu)] |"
+ " [-f test_num (1 - %zu)] | [-p] | [-k] ]\n",
cmd, ARRAY_SIZE(raw_tests), ARRAY_SIZE(get_info_tests),
ARRAY_SIZE(file_tests));
}
static int parse_args(int argc, char **argv)
{
- const char *optstr = "lpf:r:g:";
+ const char *optstr = "lpkf:r:g:";
int opt;
while ((opt = getopt(argc, argv, optstr)) != -1) {
@@ -2725,6 +2989,9 @@ static int parse_args(int argc, char **argv)
case 'p':
args.pprint_test = true;
break;
+ case 'k':
+ args.func_type_test = true;
+ break;
case 'h':
usage(argv[0]);
exit(0);
@@ -2778,6 +3045,8 @@ int main(int argc, char **argv)
if (args.always_log)
libbpf_set_print(__base_pr, __base_pr, __base_pr);
+ jit_enabled = is_jit_enabled();
+
if (args.raw_test)
err |= test_raw();
@@ -2790,8 +3059,11 @@ int main(int argc, char **argv)
if (args.pprint_test)
err |= test_pprint();
+ if (args.func_type_test)
+ err |= test_func_type();
+
if (args.raw_test || args.get_info_test || args.file_test ||
- args.pprint_test)
+ args.pprint_test || args.func_type_test)
goto done;
err |= test_raw();
--
2.17.1
^ permalink raw reply related
* [PATCH bpf-next v2 07/13] tools/bpf: add new fields for program load in lib/bpf
From: Yonghong Song @ 2018-10-17 7:23 UTC (permalink / raw)
To: ast, kafai, daniel, netdev; +Cc: kernel-team
In-Reply-To: <20181017072344.2767700-1-yhs@fb.com>
The new fields are added for program load in lib/bpf so
application uses api bpf_load_program_xattr() is able
to load program with btf and func_info data.
This functionality will be used in next patch
by bpf selftest test_btf.
Signed-off-by: Yonghong Song <yhs@fb.com>
---
tools/lib/bpf/bpf.c | 3 +++
tools/lib/bpf/bpf.h | 3 +++
2 files changed, 6 insertions(+)
diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c
index d70a255cb05e..d8d48ab34220 100644
--- a/tools/lib/bpf/bpf.c
+++ b/tools/lib/bpf/bpf.c
@@ -196,6 +196,9 @@ int bpf_load_program_xattr(const struct bpf_load_program_attr *load_attr,
attr.log_level = 0;
attr.kern_version = load_attr->kern_version;
attr.prog_ifindex = load_attr->prog_ifindex;
+ attr.prog_btf_fd = load_attr->prog_btf_fd;
+ attr.func_info_len = load_attr->func_info_len;
+ attr.func_info = ptr_to_u64(load_attr->func_info);
memcpy(attr.prog_name, load_attr->name,
min(name_len, BPF_OBJ_NAME_LEN - 1));
diff --git a/tools/lib/bpf/bpf.h b/tools/lib/bpf/bpf.h
index 258c3c178333..d2bdaffd7712 100644
--- a/tools/lib/bpf/bpf.h
+++ b/tools/lib/bpf/bpf.h
@@ -74,6 +74,9 @@ struct bpf_load_program_attr {
const char *license;
__u32 kern_version;
__u32 prog_ifindex;
+ __u32 prog_btf_fd;
+ __u32 func_info_len;
+ const struct bpf_func_info *func_info;
};
/* Flags to direct loading requirements */
--
2.17.1
^ permalink raw reply related
* [PATCH bpf-next v2 05/13] bpf: get better bpf_prog ksyms based on btf func type_id
From: Yonghong Song @ 2018-10-17 7:23 UTC (permalink / raw)
To: ast, kafai, daniel, netdev; +Cc: kernel-team
This patch added interface to load a program with the following
additional information:
. prog_btf_fd
. func_info and func_info_len
where func_info will provides function range and type_id
corresponding to each function.
If verifier agrees with function range provided by the user,
the bpf_prog ksym for each function will use the func name
provided in the type_id, which is supposed to provide better
encoding as it is not limited by 16 bytes program name
limitation and this is better for bpf program which contains
multiple subprograms.
The bpf_prog_info interface is also extended to
return btf_id and jited_func_types, so user spaces can
print out the function prototype for each jited function.
Signed-off-by: Yonghong Song <yhs@fb.com>
---
include/linux/bpf.h | 2 +
include/linux/bpf_verifier.h | 1 +
include/linux/btf.h | 2 +
include/uapi/linux/bpf.h | 11 +++++
kernel/bpf/btf.c | 16 +++++++
kernel/bpf/core.c | 10 +++++
kernel/bpf/syscall.c | 83 +++++++++++++++++++++++++++++++++++-
kernel/bpf/verifier.c | 46 ++++++++++++++++++++
8 files changed, 170 insertions(+), 1 deletion(-)
diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index e60fff48288b..a99e038ce9c4 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -308,6 +308,8 @@ struct bpf_prog_aux {
void *security;
#endif
struct bpf_prog_offload *offload;
+ struct btf *btf;
+ u32 type_id; /* type id for this prog/func */
union {
struct work_struct work;
struct rcu_head rcu;
diff --git a/include/linux/bpf_verifier.h b/include/linux/bpf_verifier.h
index 9e8056ec20fa..e84782ec50ac 100644
--- a/include/linux/bpf_verifier.h
+++ b/include/linux/bpf_verifier.h
@@ -201,6 +201,7 @@ static inline bool bpf_verifier_log_needed(const struct bpf_verifier_log *log)
struct bpf_subprog_info {
u32 start; /* insn idx of function entry point */
u16 stack_depth; /* max. stack depth used by this function */
+ u32 type_id; /* btf type_id for this subprog */
};
/* single container for all structs
diff --git a/include/linux/btf.h b/include/linux/btf.h
index e076c4697049..4611a53b5dd7 100644
--- a/include/linux/btf.h
+++ b/include/linux/btf.h
@@ -46,5 +46,7 @@ void btf_type_seq_show(const struct btf *btf, u32 type_id, void *obj,
struct seq_file *m);
int btf_get_fd_by_id(u32 id);
u32 btf_id(const struct btf *btf);
+bool btf_type_id_func(const struct btf *btf, u32 type_id);
+const char *btf_get_name_by_id(const struct btf *btf, u32 type_id);
#endif
diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
index f9187b41dff6..7ebbf4f06a65 100644
--- a/include/uapi/linux/bpf.h
+++ b/include/uapi/linux/bpf.h
@@ -332,6 +332,9 @@ union bpf_attr {
* (context accesses, allowed helpers, etc).
*/
__u32 expected_attach_type;
+ __u32 prog_btf_fd; /* fd pointing to BTF type data */
+ __u32 func_info_len; /* func_info length */
+ __aligned_u64 func_info; /* func type info */
};
struct { /* anonymous struct used by BPF_OBJ_* commands */
@@ -2585,6 +2588,9 @@ struct bpf_prog_info {
__u32 nr_jited_func_lens;
__aligned_u64 jited_ksyms;
__aligned_u64 jited_func_lens;
+ __u32 btf_id;
+ __u32 nr_jited_func_types;
+ __aligned_u64 jited_func_types;
} __attribute__((aligned(8)));
struct bpf_map_info {
@@ -2896,4 +2902,9 @@ struct bpf_flow_keys {
};
};
+struct bpf_func_info {
+ __u32 insn_offset;
+ __u32 type_id;
+};
+
#endif /* _UAPI__LINUX_BPF_H__ */
diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c
index 763f8e06bc91..9e97bbbafe9b 100644
--- a/kernel/bpf/btf.c
+++ b/kernel/bpf/btf.c
@@ -489,6 +489,15 @@ static const struct btf_type *btf_type_by_id(const struct btf *btf, u32 type_id)
return btf->types[type_id];
}
+bool btf_type_id_func(const struct btf *btf, u32 type_id)
+{
+ const struct btf_type *type = btf_type_by_id(btf, type_id);
+
+ if (!type || !btf_type_is_func(type))
+ return false;
+ return true;
+}
+
/*
* Regular int is not a bit field and it must be either
* u8/u16/u32/u64.
@@ -2582,3 +2591,10 @@ u32 btf_id(const struct btf *btf)
{
return btf->id;
}
+
+const char *btf_get_name_by_id(const struct btf *btf, u32 type_id)
+{
+ const struct btf_type *t = btf_type_by_id(btf, type_id);
+
+ return btf_name_by_offset(btf, t->name_off);
+}
diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c
index defcf4df6d91..f5ba5d4cb259 100644
--- a/kernel/bpf/core.c
+++ b/kernel/bpf/core.c
@@ -27,6 +27,7 @@
#include <linux/random.h>
#include <linux/moduleloader.h>
#include <linux/bpf.h>
+#include <linux/btf.h>
#include <linux/frame.h>
#include <linux/rbtree_latch.h>
#include <linux/kallsyms.h>
@@ -387,6 +388,7 @@ bpf_get_prog_addr_region(const struct bpf_prog *prog,
static void bpf_get_prog_name(const struct bpf_prog *prog, char *sym)
{
const char *end = sym + KSYM_NAME_LEN;
+ const char *func_name;
BUILD_BUG_ON(sizeof("bpf_prog_") +
sizeof(prog->tag) * 2 +
@@ -401,6 +403,14 @@ static void bpf_get_prog_name(const struct bpf_prog *prog, char *sym)
sym += snprintf(sym, KSYM_NAME_LEN, "bpf_prog_");
sym = bin2hex(sym, prog->tag, sizeof(prog->tag));
+
+ /* prog->aux->name will be ignored if full btf name is available */
+ if (prog->aux->btf) {
+ func_name = btf_get_name_by_id(prog->aux->btf, prog->aux->type_id);
+ snprintf(sym, (size_t)(end - sym), "_%s", func_name);
+ return;
+ }
+
if (prog->aux->name[0])
snprintf(sym, (size_t)(end - sym), "_%s", prog->aux->name);
else
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index f4ecd6ed2252..4a8b9fe150bb 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -1133,6 +1133,7 @@ static void __bpf_prog_put(struct bpf_prog *prog, bool do_idr_lock)
/* bpf_prog_free_id() must be called first */
bpf_prog_free_id(prog, do_idr_lock);
bpf_prog_kallsyms_del_all(prog);
+ btf_put(prog->aux->btf);
call_rcu(&prog->aux->rcu, __bpf_prog_put_rcu);
}
@@ -1356,8 +1357,45 @@ bpf_prog_load_check_attach_type(enum bpf_prog_type prog_type,
}
}
+static int prog_check_btf(const struct bpf_prog *prog, const struct btf *btf,
+ union bpf_attr *attr)
+{
+ struct bpf_func_info __user *uinfo, info;
+ int i, nfuncs, usize;
+ u32 prev_offset;
+
+ usize = sizeof(struct bpf_func_info);
+ if (attr->func_info_len % usize)
+ return -EINVAL;
+
+ /* func_info section should have increasing and valid insn_offset
+ * and type should be BTF_KIND_FUNC.
+ */
+ nfuncs = attr->func_info_len / usize;
+ uinfo = u64_to_user_ptr(attr->func_info);
+ for (i = 0; i < nfuncs; i++) {
+ if (copy_from_user(&info, uinfo, usize))
+ return -EFAULT;
+
+ if (!btf_type_id_func(btf, info.type_id))
+ return -EINVAL;
+
+ if (i == 0) {
+ if (info.insn_offset)
+ return -EINVAL;
+ prev_offset = 0;
+ } else if (info.insn_offset < prev_offset) {
+ return -EINVAL;
+ }
+
+ prev_offset = info.insn_offset;
+ }
+
+ return 0;
+}
+
/* last field in 'union bpf_attr' used by this command */
-#define BPF_PROG_LOAD_LAST_FIELD expected_attach_type
+#define BPF_PROG_LOAD_LAST_FIELD func_info
static int bpf_prog_load(union bpf_attr *attr)
{
@@ -1444,6 +1482,24 @@ static int bpf_prog_load(union bpf_attr *attr)
if (err)
goto free_prog;
+ if (attr->func_info_len) {
+ struct btf *btf;
+
+ btf = btf_get_by_fd(attr->prog_btf_fd);
+ if (IS_ERR(btf)) {
+ err = PTR_ERR(btf);
+ goto free_prog;
+ }
+
+ err = prog_check_btf(prog, btf, attr);
+ if (err) {
+ btf_put(btf);
+ goto free_prog;
+ }
+
+ prog->aux->btf = btf;
+ }
+
/* run eBPF verifier */
err = bpf_check(&prog, attr);
if (err < 0)
@@ -1476,6 +1532,7 @@ static int bpf_prog_load(union bpf_attr *attr)
bpf_prog_kallsyms_del_subprogs(prog);
free_used_maps(prog->aux);
free_prog:
+ btf_put(prog->aux->btf);
bpf_prog_uncharge_memlock(prog);
free_prog_sec:
security_bpf_prog_free(prog->aux);
@@ -2121,6 +2178,30 @@ static int bpf_prog_get_info_by_fd(struct bpf_prog *prog,
}
}
+ if (prog->aux->btf) {
+ info.btf_id = btf_id(prog->aux->btf);
+
+ ulen = info.nr_jited_func_types;
+ info.nr_jited_func_types = prog->aux->func_cnt;
+ if (info.nr_jited_func_types && ulen) {
+ if (bpf_dump_raw_ok()) {
+ u32 __user *user_types;
+ u32 func_type, i;
+
+ ulen = min_t(u32, info.nr_jited_func_types,
+ ulen);
+ user_types = u64_to_user_ptr(info.jited_func_types);
+ for (i = 0; i < ulen; i++) {
+ func_type = prog->aux->func[i]->aux->type_id;
+ if (put_user(func_type, &user_types[i]))
+ return -EFAULT;
+ }
+ } else {
+ info.jited_func_types = 0;
+ }
+ }
+ }
+
done:
if (copy_to_user(uinfo, &info, info_len) ||
put_user(info_len, &uattr->info.info_len))
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 3f93a548a642..01ecfe431cc2 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -4589,6 +4589,46 @@ static int check_cfg(struct bpf_verifier_env *env)
return ret;
}
+static int check_btf_func(struct bpf_prog *prog, struct bpf_verifier_env *env,
+ union bpf_attr *attr)
+{
+ struct bpf_func_info *data;
+ int i, nfuncs, ret = 0;
+
+ if (!attr->func_info_len)
+ return 0;
+
+ nfuncs = attr->func_info_len / sizeof(struct bpf_func_info);
+ if (env->subprog_cnt != nfuncs) {
+ verbose(env, "number of funcs in func_info doesn't match number of subprogs\n");
+ return -EINVAL;
+ }
+
+ data = kvmalloc(attr->func_info_len, GFP_KERNEL | __GFP_NOWARN);
+ if (!data)
+ return -ENOMEM;
+
+ if (copy_from_user(data, u64_to_user_ptr(attr->func_info),
+ attr->func_info_len)) {
+ ret = -EFAULT;
+ goto cleanup;
+ }
+
+ for (i = 0; i < nfuncs; i++) {
+ if (env->subprog_info[i].start != data[i].insn_offset) {
+ verbose(env, "func_info BTF section doesn't match subprog layout in BPF program\n");
+ ret = -EINVAL;
+ goto cleanup;
+ }
+ env->subprog_info[i].type_id = data[i].type_id;
+ }
+
+ prog->aux->type_id = data[0].type_id;
+cleanup:
+ kvfree(data);
+ return ret;
+}
+
/* check %cur's range satisfies %old's */
static bool range_within(struct bpf_reg_state *old,
struct bpf_reg_state *cur)
@@ -5873,6 +5913,8 @@ static int jit_subprogs(struct bpf_verifier_env *env)
func[i]->aux->name[0] = 'F';
func[i]->aux->stack_depth = env->subprog_info[i].stack_depth;
func[i]->jit_requested = 1;
+ func[i]->aux->btf = prog->aux->btf;
+ func[i]->aux->type_id = env->subprog_info[i].type_id;
func[i] = bpf_int_jit_compile(func[i]);
if (!func[i]->jited) {
err = -ENOTSUPP;
@@ -6307,6 +6349,10 @@ int bpf_check(struct bpf_prog **prog, union bpf_attr *attr)
if (ret < 0)
goto skip_full_check;
+ ret = check_btf_func(env->prog, env, attr);
+ if (ret < 0)
+ goto skip_full_check;
+
ret = do_check(env);
if (env->cur_state) {
free_verifier_state(env->cur_state, true);
--
2.17.1
^ permalink raw reply related
* [PATCH bpf-next v2 09/13] tools/bpf: add support to read .BTF.ext sections
From: Yonghong Song @ 2018-10-17 7:23 UTC (permalink / raw)
To: ast, kafai, daniel, netdev; +Cc: kernel-team
In-Reply-To: <20181017072344.2767700-1-yhs@fb.com>
The .BTF section is already available to encode types.
These types can be used for map
pretty print. The whole .BTF will be passed to the
kernel as well for which kernel can verify and return
to the user space for pretty print etc.
The llvm patch at https://reviews.llvm.org/D53261
will generate .BTF section and one more section
.BTF.ext. The .BTF.ext section encodes function type
information and line information. For line information,
the actual source code is encoded in the section, which
makes compiler itself as an ideal place for section
generation.
The .BTF section does not depend on any other section,
and .BTF.ext has dependency on .BTF for strings and types.
The .BTF section can be directly loaded into the
kernel, and the .BTF.ext section cannot. The loader
may need to do some relocation and merging,
similar to merging multiple code sections, before
loading into the kernel.
In this patch, only func type info is processed.
The functionality is implemented in libbpf.
Signed-off-by: Yonghong Song <yhs@fb.com>
---
tools/lib/bpf/btf.c | 232 +++++++++++++++++++++++++++++++++++++++++
tools/lib/bpf/btf.h | 31 ++++++
tools/lib/bpf/libbpf.c | 53 +++++++++-
3 files changed, 312 insertions(+), 4 deletions(-)
diff --git a/tools/lib/bpf/btf.c b/tools/lib/bpf/btf.c
index 33095fc1860b..4748e0bacd2b 100644
--- a/tools/lib/bpf/btf.c
+++ b/tools/lib/bpf/btf.c
@@ -37,6 +37,11 @@ struct btf {
int fd;
};
+struct btf_ext {
+ void *func_info;
+ __u32 func_info_len;
+};
+
static int btf_add_type(struct btf *btf, struct btf_type *t)
{
if (btf->types_size - btf->nr_types < 2) {
@@ -397,3 +402,230 @@ const char *btf__name_by_offset(const struct btf *btf, __u32 offset)
else
return NULL;
}
+
+static int btf_ext_validate_func_info(const struct btf_sec_func_info *sinfo,
+ __u32 size, btf_print_fn_t err_log)
+{
+ int sec_hdrlen = sizeof(struct btf_sec_func_info);
+ __u32 record_size = sizeof(struct bpf_func_info);
+ __u32 size_left = size, num_records;
+ __u64 total_record_size;
+
+ while (size_left) {
+ if (size_left < sec_hdrlen) {
+ elog("BTF.ext func_info header not found");
+ return -EINVAL;
+ }
+
+ num_records = sinfo->num_func_info;
+ if (num_records == 0) {
+ elog("incorrect BTF.ext num_func_info");
+ return -EINVAL;
+ }
+
+ total_record_size = sec_hdrlen +
+ (__u64)num_records * record_size;
+ if (size_left < total_record_size) {
+ elog("incorrect BTF.ext num_func_info");
+ return -EINVAL;
+ }
+
+ size_left -= total_record_size;
+ sinfo = (void *)sinfo + total_record_size;
+ }
+
+ return 0;
+}
+static int btf_ext_parse_hdr(__u8 *data, __u32 data_size,
+ btf_print_fn_t err_log)
+{
+ const struct btf_ext_header *hdr = (struct btf_ext_header *)data;
+ const struct btf_sec_func_info *sinfo;
+ __u32 meta_left, last_func_info_pos;
+
+ if (data_size < sizeof(*hdr)) {
+ elog("BTF.ext header not found");
+ return -EINVAL;
+ }
+
+ if (hdr->magic != BTF_MAGIC) {
+ elog("Invalid BTF.ext magic:%x\n", hdr->magic);
+ return -EINVAL;
+ }
+
+ if (hdr->version != BTF_VERSION) {
+ elog("Unsupported BTF.ext version:%u\n", hdr->version);
+ return -ENOTSUP;
+ }
+
+ if (hdr->flags) {
+ elog("Unsupported BTF.ext flags:%x\n", hdr->flags);
+ return -ENOTSUP;
+ }
+
+ meta_left = data_size - sizeof(*hdr);
+ if (!meta_left) {
+ elog("BTF.ext has no data\n");
+ return -EINVAL;
+ }
+
+ if (meta_left < hdr->func_info_off) {
+ elog("Invalid BTF.ext func_info section offset:%u\n",
+ hdr->func_info_off);
+ return -EINVAL;
+ }
+
+ if (hdr->func_info_off & 0x02) {
+ elog("BTF.ext func_info section is not aligned to 4 bytes\n");
+ return -EINVAL;
+ }
+
+ last_func_info_pos = sizeof(*hdr) + hdr->func_info_off +
+ hdr->func_info_len;
+ if (last_func_info_pos > data_size) {
+ elog("Invalid BTF.ext func_info section size:%u\n",
+ hdr->func_info_len);
+ return -EINVAL;
+ }
+
+ sinfo = (const struct btf_sec_func_info *)(data + sizeof(*hdr) +
+ hdr->func_info_off);
+ return btf_ext_validate_func_info(sinfo, hdr->func_info_len,
+ err_log);
+}
+
+void btf_ext__free(struct btf_ext *btf_ext)
+{
+ if (!btf_ext)
+ return;
+
+ free(btf_ext->func_info);
+ free(btf_ext);
+}
+
+struct btf_ext *btf_ext__new(__u8 *data, __u32 size, btf_print_fn_t err_log)
+{
+ int hdrlen = sizeof(struct btf_ext_header);
+ const struct btf_ext_header *hdr;
+ struct btf_ext *btf_ext;
+ void *fdata;
+ int err;
+
+ err = btf_ext_parse_hdr(data, size, err_log);
+ if (err)
+ return ERR_PTR(err);
+
+ btf_ext = calloc(1, sizeof(struct btf_ext));
+ if (!btf_ext)
+ return ERR_PTR(-ENOMEM);
+
+ hdr = (const struct btf_ext_header *)data;
+ fdata = malloc(hdr->func_info_len);
+ if (!fdata)
+ return ERR_PTR(-ENOMEM);
+
+ memcpy(fdata, data + hdrlen + hdr->func_info_off, hdr->func_info_len);
+ btf_ext->func_info = fdata;
+ btf_ext->func_info_len = hdr->func_info_len;
+
+ return btf_ext;
+}
+
+int btf_ext_reloc_init(struct btf *btf, struct btf_ext *btf_ext,
+ const char *sec_name, __u32 *btf_fd,
+ void **func_info, __u32 *func_info_len)
+{
+ int sec_hdrlen = sizeof(struct btf_sec_func_info);
+ int record_len = sizeof(struct bpf_func_info);
+ struct btf_sec_func_info *sinfo;
+ int i, remain_len, records_len;
+ const char *info_sec_name;
+ void *data;
+
+ if (!btf || !btf_ext) {
+ *btf_fd = 0;
+ *func_info = NULL;
+ *func_info_len = 0;
+ return 0;
+ }
+
+ sinfo = btf_ext->func_info;
+ remain_len = btf_ext->func_info_len;
+ *btf_fd = btf__fd(btf);
+
+ while (remain_len > 0) {
+ records_len = sinfo->num_func_info * record_len;
+ info_sec_name = btf__name_by_offset(btf, sinfo->sec_name_off);
+ if (strcmp(info_sec_name, sec_name)) {
+ remain_len -= sec_hdrlen + records_len;
+ sinfo = (void *)sinfo + sec_hdrlen + records_len;
+ continue;
+ }
+
+ data = malloc(records_len);
+ if (!data)
+ return -ENOMEM;
+
+ memcpy(data, sinfo->data, records_len);
+
+ /* adjust the insn_offset, the data in .BTF.ext is
+ * the actual byte offset, and the kernel expects
+ * the offset in term of bpf_insn.
+ */
+ for (i = 0; i < sinfo->num_func_info; i++)
+ ((struct bpf_func_info *)data)[i].insn_offset
+ /= sizeof(struct bpf_insn);
+
+ *func_info = data;
+ *func_info_len = records_len;
+ break;
+ }
+
+ return 0;
+}
+
+int btf_ext_reloc(struct btf *btf, struct btf_ext *btf_ext,
+ const char *sec_name, __u32 insns_cnt,
+ void **func_info, __u32 *func_info_len)
+{
+ int sec_hdrlen = sizeof(struct btf_sec_func_info);
+ int record_len = sizeof(struct bpf_func_info);
+ __u32 i, remain_len, records_len;
+ struct btf_sec_func_info *sinfo;
+ struct bpf_func_info *record;
+ const char *info_sec_name;
+ __u32 existing_flen;
+ void *data;
+
+ if (!*func_info)
+ return 0;
+
+ sinfo = btf_ext->func_info;
+ remain_len = btf_ext->func_info_len;
+ while (remain_len > 0) {
+ records_len = sinfo->num_func_info * record_len;
+ info_sec_name = btf__name_by_offset(btf, sinfo->sec_name_off);
+ if (strcmp(info_sec_name, sec_name)) {
+ remain_len -= sec_hdrlen + records_len;
+ sinfo = (void *)sinfo + sec_hdrlen + records_len;
+ continue;
+ }
+
+ existing_flen = *func_info_len;
+ data = realloc(*func_info, existing_flen + records_len);
+ if (!data)
+ return -ENOMEM;
+
+ memcpy(data + existing_flen, sinfo->data, records_len);
+ record = data + existing_flen;
+ for (i = 0; i < sinfo->num_func_info; i++)
+ record[i].insn_offset =
+ record[i].insn_offset/sizeof(struct bpf_insn) +
+ insns_cnt;
+ *func_info = data;
+ *func_info_len = existing_flen + records_len;
+ break;
+ }
+
+ return 0;
+}
diff --git a/tools/lib/bpf/btf.h b/tools/lib/bpf/btf.h
index b77e7080f7e7..8758098a7991 100644
--- a/tools/lib/bpf/btf.h
+++ b/tools/lib/bpf/btf.h
@@ -11,10 +11,32 @@
#endif
#define BTF_ELF_SEC ".BTF"
+#define BTF_EXT_ELF_SEC ".BTF.ext"
struct btf;
+struct btf_ext;
struct btf_type;
+struct btf_ext_header {
+ __u16 magic;
+ __u8 version;
+ __u8 flags;
+ __u32 hdr_len;
+
+ /* All offsets are in bytes relative to the end of this header */
+ __u32 func_info_off;
+ __u32 func_info_len;
+ __u32 line_info_off;
+ __u32 line_info_len;
+};
+
+struct btf_sec_func_info {
+ __u32 sec_name_off;
+ __u32 num_func_info;
+ /* followed by num_func_info number of bpf_func_info records */
+ __u8 data[0];
+};
+
typedef int (*btf_print_fn_t)(const char *, ...)
__attribute__((format(printf, 1, 2)));
@@ -29,4 +51,13 @@ LIBBPF_API int btf__resolve_type(const struct btf *btf, __u32 type_id);
LIBBPF_API int btf__fd(const struct btf *btf);
LIBBPF_API const char *btf__name_by_offset(const struct btf *btf, __u32 offset);
+struct btf_ext *btf_ext__new(__u8 *data, __u32 size, btf_print_fn_t err_log);
+void btf_ext__free(struct btf_ext *btf_ext);
+int btf_ext_reloc_init(struct btf *btf, struct btf_ext *btf_ext,
+ const char *sec_name, __u32 *btf_fd,
+ void **func_info, __u32 *func_info_len);
+int btf_ext_reloc(struct btf *btf, struct btf_ext *btf_ext,
+ const char *sec_name, __u32 insns_cnt, void **func_info,
+ __u32 *func_info_len);
+
#endif /* __LIBBPF_BTF_H */
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index bd71efcc53be..2ea3b1467d47 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -151,6 +151,9 @@ struct bpf_program {
bpf_program_clear_priv_t clear_priv;
enum bpf_attach_type expected_attach_type;
+ __u32 btf_fd;
+ void *func_info;
+ __u32 func_info_len;
};
struct bpf_map {
@@ -207,6 +210,7 @@ struct bpf_object {
struct list_head list;
struct btf *btf;
+ struct btf_ext *btf_ext;
void *priv;
bpf_object_clear_priv_t clear_priv;
@@ -783,6 +787,15 @@ static int bpf_object__elf_collect(struct bpf_object *obj, int flags)
BTF_ELF_SEC, PTR_ERR(obj->btf));
obj->btf = NULL;
}
+ } else if (strcmp(name, BTF_EXT_ELF_SEC) == 0) {
+ obj->btf_ext = btf_ext__new(data->d_buf, data->d_size,
+ __pr_debug);
+ if (IS_ERR(obj->btf_ext)) {
+ pr_warning("Error loading ELF section %s: %ld. Ignored and continue.\n",
+ BTF_EXT_ELF_SEC,
+ PTR_ERR(obj->btf_ext));
+ obj->btf_ext = NULL;
+ }
} else if (sh.sh_type == SHT_SYMTAB) {
if (obj->efile.symbols) {
pr_warning("bpf: multiple SYMTAB in %s\n",
@@ -1166,6 +1179,7 @@ bpf_program__reloc_text(struct bpf_program *prog, struct bpf_object *obj,
struct bpf_insn *insn, *new_insn;
struct bpf_program *text;
size_t new_cnt;
+ int err;
if (relo->type != RELO_CALL)
return -LIBBPF_ERRNO__RELOC;
@@ -1188,6 +1202,16 @@ bpf_program__reloc_text(struct bpf_program *prog, struct bpf_object *obj,
pr_warning("oom in prog realloc\n");
return -ENOMEM;
}
+
+ err = btf_ext_reloc(obj->btf, obj->btf_ext, text->section_name,
+ prog->insns_cnt, &prog->func_info,
+ &prog->func_info_len);
+ if (err) {
+ pr_warning("error in btf_ext_reloc for sec %s\n",
+ text->section_name);
+ return err;
+ }
+
memcpy(new_insn + prog->insns_cnt, text->insns,
text->insns_cnt * sizeof(*insn));
prog->insns = new_insn;
@@ -1207,7 +1231,19 @@ bpf_program__relocate(struct bpf_program *prog, struct bpf_object *obj)
{
int i, err;
- if (!prog || !prog->reloc_desc)
+ if (!prog)
+ return 0;
+
+ err = btf_ext_reloc_init(obj->btf, obj->btf_ext, prog->section_name,
+ &prog->btf_fd, &prog->func_info,
+ &prog->func_info_len);
+ if (err) {
+ pr_warning("err in btf_ext_reloc_init for sec %s\n",
+ prog->section_name);
+ return err;
+ }
+
+ if (!prog->reloc_desc)
return 0;
for (i = 0; i < prog->nr_reloc; i++) {
@@ -1297,7 +1333,8 @@ static int bpf_object__collect_reloc(struct bpf_object *obj)
static int
load_program(enum bpf_prog_type type, enum bpf_attach_type expected_attach_type,
const char *name, struct bpf_insn *insns, int insns_cnt,
- char *license, __u32 kern_version, int *pfd, int prog_ifindex)
+ char *license, __u32 kern_version, int *pfd, int prog_ifindex,
+ u32 btf_fd, struct bpf_func_info *func_info, u32 func_info_len)
{
struct bpf_load_program_attr load_attr;
char *cp, errmsg[STRERR_BUFSIZE];
@@ -1313,6 +1350,9 @@ load_program(enum bpf_prog_type type, enum bpf_attach_type expected_attach_type,
load_attr.license = license;
load_attr.kern_version = kern_version;
load_attr.prog_ifindex = prog_ifindex;
+ load_attr.prog_btf_fd = btf_fd;
+ load_attr.func_info = func_info;
+ load_attr.func_info_len = func_info_len;
if (!load_attr.insns || !load_attr.insns_cnt)
return -EINVAL;
@@ -1396,7 +1436,9 @@ bpf_program__load(struct bpf_program *prog,
err = load_program(prog->type, prog->expected_attach_type,
prog->name, prog->insns, prog->insns_cnt,
license, kern_version, &fd,
- prog->prog_ifindex);
+ prog->prog_ifindex,
+ prog->btf_fd, prog->func_info,
+ prog->func_info_len);
if (!err)
prog->instances.fds[0] = fd;
goto out;
@@ -1428,7 +1470,9 @@ bpf_program__load(struct bpf_program *prog,
prog->name, result.new_insn_ptr,
result.new_insn_cnt,
license, kern_version, &fd,
- prog->prog_ifindex);
+ prog->prog_ifindex,
+ prog->btf_fd, prog->func_info,
+ prog->func_info_len);
if (err) {
pr_warning("Loading the %dth instance of program '%s' failed\n",
@@ -1844,6 +1888,7 @@ void bpf_object__close(struct bpf_object *obj)
bpf_object__elf_finish(obj);
bpf_object__unload(obj);
btf__free(obj->btf);
+ btf_ext__free(obj->btf_ext);
for (i = 0; i < obj->nr_maps; i++) {
zfree(&obj->maps[i].name);
--
2.17.1
^ permalink raw reply related
* [PATCH bpf-next v2 06/13] tools/bpf: sync kernel uapi bpf.h header to tools directory
From: Yonghong Song @ 2018-10-17 7:23 UTC (permalink / raw)
To: ast, kafai, daniel, netdev; +Cc: kernel-team
In-Reply-To: <20181017072344.2767700-1-yhs@fb.com>
The kernel uapi bpf.h is synced to tools directory.
Signed-off-by: Yonghong Song <yhs@fb.com>
---
tools/include/uapi/linux/bpf.h | 11 +++++++++++
1 file changed, 11 insertions(+)
diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h
index f9187b41dff6..7ebbf4f06a65 100644
--- a/tools/include/uapi/linux/bpf.h
+++ b/tools/include/uapi/linux/bpf.h
@@ -332,6 +332,9 @@ union bpf_attr {
* (context accesses, allowed helpers, etc).
*/
__u32 expected_attach_type;
+ __u32 prog_btf_fd; /* fd pointing to BTF type data */
+ __u32 func_info_len; /* func_info length */
+ __aligned_u64 func_info; /* func type info */
};
struct { /* anonymous struct used by BPF_OBJ_* commands */
@@ -2585,6 +2588,9 @@ struct bpf_prog_info {
__u32 nr_jited_func_lens;
__aligned_u64 jited_ksyms;
__aligned_u64 jited_func_lens;
+ __u32 btf_id;
+ __u32 nr_jited_func_types;
+ __aligned_u64 jited_func_types;
} __attribute__((aligned(8)));
struct bpf_map_info {
@@ -2896,4 +2902,9 @@ struct bpf_flow_keys {
};
};
+struct bpf_func_info {
+ __u32 insn_offset;
+ __u32 type_id;
+};
+
#endif /* _UAPI__LINUX_BPF_H__ */
--
2.17.1
^ permalink raw reply related
* [PATCH bpf-next v2 11/13] tools/bpf: refactor to implement btf_get_from_id() in lib/bpf
From: Yonghong Song @ 2018-10-17 7:23 UTC (permalink / raw)
To: ast, kafai, daniel, netdev; +Cc: kernel-team
In-Reply-To: <20181017072400.2768484-1-yhs@fb.com>
The function get_btf() is implemented in tools/bpf/bpftool/map.c
to get a btf structure given a map_info. This patch
refactored this function to be function btf_get_from_id()
in tools/lib/bpf so that it can be used later.
Signed-off-by: Yonghong Song <yhs@fb.com>
---
tools/bpf/bpftool/map.c | 68 ++--------------------------------------
tools/lib/bpf/btf.c | 69 +++++++++++++++++++++++++++++++++++++++++
tools/lib/bpf/btf.h | 18 ++++++-----
3 files changed, 81 insertions(+), 74 deletions(-)
diff --git a/tools/bpf/bpftool/map.c b/tools/bpf/bpftool/map.c
index 7bf38f0e152e..1b8a75fa0471 100644
--- a/tools/bpf/bpftool/map.c
+++ b/tools/bpf/bpftool/map.c
@@ -215,70 +215,6 @@ static int do_dump_btf(const struct btf_dumper *d,
return ret;
}
-static int get_btf(struct bpf_map_info *map_info, struct btf **btf)
-{
- struct bpf_btf_info btf_info = { 0 };
- __u32 len = sizeof(btf_info);
- __u32 last_size;
- int btf_fd;
- void *ptr;
- int err;
-
- err = 0;
- *btf = NULL;
- btf_fd = bpf_btf_get_fd_by_id(map_info->btf_id);
- if (btf_fd < 0)
- return 0;
-
- /* we won't know btf_size until we call bpf_obj_get_info_by_fd(). so
- * let's start with a sane default - 4KiB here - and resize it only if
- * bpf_obj_get_info_by_fd() needs a bigger buffer.
- */
- btf_info.btf_size = 4096;
- last_size = btf_info.btf_size;
- ptr = malloc(last_size);
- if (!ptr) {
- err = -ENOMEM;
- goto exit_free;
- }
-
- bzero(ptr, last_size);
- btf_info.btf = ptr_to_u64(ptr);
- err = bpf_obj_get_info_by_fd(btf_fd, &btf_info, &len);
-
- if (!err && btf_info.btf_size > last_size) {
- void *temp_ptr;
-
- last_size = btf_info.btf_size;
- temp_ptr = realloc(ptr, last_size);
- if (!temp_ptr) {
- err = -ENOMEM;
- goto exit_free;
- }
- ptr = temp_ptr;
- bzero(ptr, last_size);
- btf_info.btf = ptr_to_u64(ptr);
- err = bpf_obj_get_info_by_fd(btf_fd, &btf_info, &len);
- }
-
- if (err || btf_info.btf_size > last_size) {
- err = errno;
- goto exit_free;
- }
-
- *btf = btf__new((__u8 *)btf_info.btf, btf_info.btf_size, NULL);
- if (IS_ERR(*btf)) {
- err = PTR_ERR(*btf);
- *btf = NULL;
- }
-
-exit_free:
- close(btf_fd);
- free(ptr);
-
- return err;
-}
-
static json_writer_t *get_btf_writer(void)
{
json_writer_t *jw = jsonw_new(stdout);
@@ -765,7 +701,7 @@ static int do_dump(int argc, char **argv)
prev_key = NULL;
- err = get_btf(&info, &btf);
+ err = btf_get_from_id(info.btf_id, &btf);
if (err) {
p_err("failed to get btf");
goto exit_free;
@@ -909,7 +845,7 @@ static int do_lookup(int argc, char **argv)
}
/* here means bpf_map_lookup_elem() succeeded */
- err = get_btf(&info, &btf);
+ err = btf_get_from_id(info.btf_id, &btf);
if (err) {
p_err("failed to get btf");
goto exit_free;
diff --git a/tools/lib/bpf/btf.c b/tools/lib/bpf/btf.c
index 4748e0bacd2b..ab654628e966 100644
--- a/tools/lib/bpf/btf.c
+++ b/tools/lib/bpf/btf.c
@@ -42,6 +42,11 @@ struct btf_ext {
__u32 func_info_len;
};
+static inline __u64 ptr_to_u64(const void *ptr)
+{
+ return (__u64) (unsigned long) ptr;
+}
+
static int btf_add_type(struct btf *btf, struct btf_type *t)
{
if (btf->types_size - btf->nr_types < 2) {
@@ -403,6 +408,70 @@ const char *btf__name_by_offset(const struct btf *btf, __u32 offset)
return NULL;
}
+int btf_get_from_id(__u32 id, struct btf **btf)
+{
+ struct bpf_btf_info btf_info = { 0 };
+ __u32 len = sizeof(btf_info);
+ __u32 last_size;
+ int btf_fd;
+ void *ptr;
+ int err;
+
+ err = 0;
+ *btf = NULL;
+ btf_fd = bpf_btf_get_fd_by_id(id);
+ if (btf_fd < 0)
+ return 0;
+
+ /* we won't know btf_size until we call bpf_obj_get_info_by_fd(). so
+ * let's start with a sane default - 4KiB here - and resize it only if
+ * bpf_obj_get_info_by_fd() needs a bigger buffer.
+ */
+ btf_info.btf_size = 4096;
+ last_size = btf_info.btf_size;
+ ptr = malloc(last_size);
+ if (!ptr) {
+ err = -ENOMEM;
+ goto exit_free;
+ }
+
+ bzero(ptr, last_size);
+ btf_info.btf = ptr_to_u64(ptr);
+ err = bpf_obj_get_info_by_fd(btf_fd, &btf_info, &len);
+
+ if (!err && btf_info.btf_size > last_size) {
+ void *temp_ptr;
+
+ last_size = btf_info.btf_size;
+ temp_ptr = realloc(ptr, last_size);
+ if (!temp_ptr) {
+ err = -ENOMEM;
+ goto exit_free;
+ }
+ ptr = temp_ptr;
+ bzero(ptr, last_size);
+ btf_info.btf = ptr_to_u64(ptr);
+ err = bpf_obj_get_info_by_fd(btf_fd, &btf_info, &len);
+ }
+
+ if (err || btf_info.btf_size > last_size) {
+ err = errno;
+ goto exit_free;
+ }
+
+ *btf = btf__new((__u8 *)btf_info.btf, btf_info.btf_size, NULL);
+ if (IS_ERR(*btf)) {
+ err = PTR_ERR(*btf);
+ *btf = NULL;
+ }
+
+exit_free:
+ close(btf_fd);
+ free(ptr);
+
+ return err;
+}
+
static int btf_ext_validate_func_info(const struct btf_sec_func_info *sinfo,
__u32 size, btf_print_fn_t err_log)
{
diff --git a/tools/lib/bpf/btf.h b/tools/lib/bpf/btf.h
index 8758098a7991..975c8d2f43cb 100644
--- a/tools/lib/bpf/btf.h
+++ b/tools/lib/bpf/btf.h
@@ -50,14 +50,16 @@ LIBBPF_API __s64 btf__resolve_size(const struct btf *btf, __u32 type_id);
LIBBPF_API int btf__resolve_type(const struct btf *btf, __u32 type_id);
LIBBPF_API int btf__fd(const struct btf *btf);
LIBBPF_API const char *btf__name_by_offset(const struct btf *btf, __u32 offset);
+LIBBPF_API int btf_get_from_id(__u32 id, struct btf **btf);
-struct btf_ext *btf_ext__new(__u8 *data, __u32 size, btf_print_fn_t err_log);
-void btf_ext__free(struct btf_ext *btf_ext);
-int btf_ext_reloc_init(struct btf *btf, struct btf_ext *btf_ext,
- const char *sec_name, __u32 *btf_fd,
- void **func_info, __u32 *func_info_len);
-int btf_ext_reloc(struct btf *btf, struct btf_ext *btf_ext,
- const char *sec_name, __u32 insns_cnt, void **func_info,
- __u32 *func_info_len);
+LIBBPF_API struct btf_ext *btf_ext__new(__u8 *data, __u32 size,
+ btf_print_fn_t err_log);
+LIBBPF_API void btf_ext__free(struct btf_ext *btf_ext);
+LIBBPF_API int btf_ext_reloc_init(struct btf *btf, struct btf_ext *btf_ext,
+ const char *sec_name, __u32 *btf_fd,
+ void **func_info, __u32 *func_info_len);
+LIBBPF_API int btf_ext_reloc(struct btf *btf, struct btf_ext *btf_ext,
+ const char *sec_name, __u32 insns_cnt,
+ void **func_info, __u32 *func_info_len);
#endif /* __LIBBPF_BTF_H */
--
2.17.1
^ permalink raw reply related
* [PATCH bpf-next v2 13/13] tools/bpf: bpftool: add support for jited func types
From: Yonghong Song @ 2018-10-17 7:24 UTC (permalink / raw)
To: ast, kafai, daniel, netdev; +Cc: kernel-team
In-Reply-To: <20181017072400.2768484-1-yhs@fb.com>
This patch added support to print function signature
if btf func_info is available. Note that ksym
now uses function name instead of prog_name as
prog_name has a limit of 16 bytes including
ending '\0'.
The following is a sample output for selftests
test_btf with file test_btf_haskv.o:
$ bpftool prog dump jited id 1
int _dummy_tracepoint(struct dummy_tracepoint_args * ):
bpf_prog_b07ccb89267cf242__dummy_tracepoint:
0: push %rbp
1: mov %rsp,%rbp
......
3c: add $0x28,%rbp
40: leaveq
41: retq
int test_long_fname_1(struct dummy_tracepoint_args * ):
bpf_prog_2dcecc18072623fc_test_long_fname_1:
0: push %rbp
1: mov %rsp,%rbp
......
3a: add $0x28,%rbp
3e: leaveq
3f: retq
int test_long_fname_2(struct dummy_tracepoint_args * ):
bpf_prog_89d64e4abf0f0126_test_long_fname_2:
0: push %rbp
1: mov %rsp,%rbp
......
80: add $0x28,%rbp
84: leaveq
85: retq
Signed-off-by: Yonghong Song <yhs@fb.com>
---
tools/bpf/bpftool/btf_dumper.c | 96 ++++++++++++++++++++++++++++++++++
tools/bpf/bpftool/main.h | 2 +
tools/bpf/bpftool/prog.c | 54 +++++++++++++++++++
3 files changed, 152 insertions(+)
diff --git a/tools/bpf/bpftool/btf_dumper.c b/tools/bpf/bpftool/btf_dumper.c
index 55bc512a1831..a31df4202335 100644
--- a/tools/bpf/bpftool/btf_dumper.c
+++ b/tools/bpf/bpftool/btf_dumper.c
@@ -249,3 +249,99 @@ int btf_dumper_type(const struct btf_dumper *d, __u32 type_id,
{
return btf_dumper_do_type(d, type_id, 0, data);
}
+
+#define BTF_PRINT_STRING(str) \
+ { \
+ pos += snprintf(func_sig + pos, size - pos, str); \
+ if (pos >= size) \
+ return -1; \
+ }
+#define BTF_PRINT_ONE_ARG(fmt, arg) \
+ { \
+ pos += snprintf(func_sig + pos, size - pos, fmt, arg); \
+ if (pos >= size) \
+ return -1; \
+ }
+#define BTF_PRINT_TYPE_ONLY(type) \
+ { \
+ pos = __btf_dumper_type_only(btf, type, func_sig, \
+ pos, size); \
+ if (pos == -1) \
+ return -1; \
+ }
+
+static int __btf_dumper_type_only(struct btf *btf, __u32 type_id,
+ char *func_sig, int pos, int size)
+{
+ const struct btf_type *t = btf__type_by_id(btf, type_id);
+ const struct btf_array *array;
+ int i, vlen;
+
+ switch (BTF_INFO_KIND(t->info)) {
+ case BTF_KIND_INT:
+ BTF_PRINT_ONE_ARG("%s ",
+ btf__name_by_offset(btf, t->name_off));
+ break;
+ case BTF_KIND_STRUCT:
+ BTF_PRINT_ONE_ARG("struct %s ",
+ btf__name_by_offset(btf, t->name_off));
+ break;
+ case BTF_KIND_UNION:
+ BTF_PRINT_ONE_ARG("union %s ",
+ btf__name_by_offset(btf, t->name_off));
+ break;
+ case BTF_KIND_ENUM:
+ BTF_PRINT_ONE_ARG("enum %s ",
+ btf__name_by_offset(btf, t->name_off));
+ break;
+ case BTF_KIND_ARRAY:
+ array = (struct btf_array *)(t + 1);
+ BTF_PRINT_TYPE_ONLY(array->type);
+ BTF_PRINT_ONE_ARG("[%d]", array->nelems);
+ break;
+ case BTF_KIND_PTR:
+ BTF_PRINT_TYPE_ONLY(t->type);
+ BTF_PRINT_STRING("* ");
+ break;
+ case BTF_KIND_UNKN:
+ case BTF_KIND_FWD:
+ case BTF_KIND_TYPEDEF:
+ return -1;
+ case BTF_KIND_VOLATILE:
+ BTF_PRINT_STRING("volatile ");
+ BTF_PRINT_TYPE_ONLY(t->type);
+ break;
+ case BTF_KIND_CONST:
+ BTF_PRINT_STRING("const ");
+ BTF_PRINT_TYPE_ONLY(t->type);
+ break;
+ case BTF_KIND_RESTRICT:
+ BTF_PRINT_STRING("restrict ");
+ BTF_PRINT_TYPE_ONLY(t->type);
+ break;
+ case BTF_KIND_FUNC:
+ case BTF_KIND_FUNC_PROTO:
+ BTF_PRINT_TYPE_ONLY(t->type);
+ BTF_PRINT_ONE_ARG("%s(", btf__name_by_offset(btf, t->name_off));
+ vlen = BTF_INFO_VLEN(t->info);
+ for (i = 0; i < vlen; i++) {
+ __u32 arg_type = ((__u32 *)(t + 1))[i];
+
+ BTF_PRINT_TYPE_ONLY(arg_type);
+ if (i != (vlen - 1))
+ BTF_PRINT_STRING(", ");
+ }
+ BTF_PRINT_STRING(")");
+ break;
+ default:
+ return -1;
+ }
+
+ return pos;
+}
+
+int btf_dumper_type_only(struct btf *btf, __u32 type_id, char *func_sig,
+ int size)
+{
+ return __btf_dumper_type_only(btf, type_id, func_sig, 0, size);
+}
diff --git a/tools/bpf/bpftool/main.h b/tools/bpf/bpftool/main.h
index 28ee769bd11b..f887564476dc 100644
--- a/tools/bpf/bpftool/main.h
+++ b/tools/bpf/bpftool/main.h
@@ -168,6 +168,8 @@ struct btf_dumper {
*/
int btf_dumper_type(const struct btf_dumper *d, __u32 type_id,
const void *data);
+int btf_dumper_type_only(struct btf *btf, __u32 func_type_id, char *func_only,
+ int size);
struct nlattr;
struct ifinfomsg;
diff --git a/tools/bpf/bpftool/prog.c b/tools/bpf/bpftool/prog.c
index 335028968dfb..e78632a30ea3 100644
--- a/tools/bpf/bpftool/prog.c
+++ b/tools/bpf/bpftool/prog.c
@@ -47,6 +47,7 @@
#include <linux/err.h>
#include <bpf.h>
+#include <btf.h>
#include <libbpf.h>
#include "cfg.h"
@@ -447,9 +448,11 @@ static int do_show(int argc, char **argv)
static int do_dump(int argc, char **argv)
{
unsigned long *func_ksyms = NULL;
+ unsigned int *func_types = NULL;
struct bpf_prog_info info = {};
unsigned int *func_lens = NULL;
unsigned int nr_func_ksyms;
+ unsigned int nr_func_types;
unsigned int nr_func_lens;
struct dump_data dd = {};
__u32 len = sizeof(info);
@@ -546,6 +549,16 @@ static int do_dump(int argc, char **argv)
}
}
+ nr_func_types = info.nr_jited_func_types;
+ if (nr_func_types) {
+ func_types = malloc(nr_func_types * sizeof(__u32));
+ if (!func_types) {
+ p_err("mem alloc failed");
+ close(fd);
+ goto err_free;
+ }
+ }
+
memset(&info, 0, sizeof(info));
*member_ptr = ptr_to_u64(buf);
@@ -554,6 +567,8 @@ static int do_dump(int argc, char **argv)
info.nr_jited_ksyms = nr_func_ksyms;
info.jited_func_lens = ptr_to_u64(func_lens);
info.nr_jited_func_lens = nr_func_lens;
+ info.jited_func_types = ptr_to_u64(func_types);
+ info.nr_jited_func_types = nr_func_types;
err = bpf_obj_get_info_by_fd(fd, &info, &len);
close(fd);
@@ -577,6 +592,11 @@ static int do_dump(int argc, char **argv)
goto err_free;
}
+ if (info.nr_jited_func_types > nr_func_types) {
+ p_err("too many types returned");
+ goto err_free;
+ }
+
if ((member_len == &info.jited_prog_len &&
info.jited_prog_insns == 0) ||
(member_len == &info.xlated_prog_len &&
@@ -585,6 +605,12 @@ static int do_dump(int argc, char **argv)
goto err_free;
}
+ if (info.btf_id &&
+ info.nr_jited_func_lens != info.nr_jited_func_types) {
+ p_err("unequal jited func lens and types");
+ goto err_free;
+ }
+
if (filepath) {
fd = open(filepath, O_WRONLY | O_CREAT | O_TRUNC, 0600);
if (fd < 0) {
@@ -618,7 +644,9 @@ static int do_dump(int argc, char **argv)
struct kernel_sym *sym = NULL;
char sym_name[SYM_MAX_NAME];
unsigned char *img = buf;
+ struct btf *btf = NULL;
__u64 *ksyms = NULL;
+ char func_sig[1024];
__u32 *lens;
__u32 i;
@@ -627,6 +655,14 @@ static int do_dump(int argc, char **argv)
ksyms = (__u64 *) info.jited_ksyms;
}
+ if (info.btf_id) {
+ err = btf_get_from_id(info.btf_id, &btf);
+ if (err) {
+ p_err("failed to get btf");
+ goto err_free;
+ }
+ }
+
if (json_output)
jsonw_start_array(json_wtr);
@@ -642,12 +678,28 @@ static int do_dump(int argc, char **argv)
strcpy(sym_name, "unknown");
}
+ func_sig[0] = '\0';
+ if (btf) {
+ err = btf_dumper_type_only(btf,
+ func_types[i],
+ func_sig,
+ sizeof(func_sig));
+ if (err < 0)
+ func_sig[0] = '\0';
+ }
+
if (json_output) {
jsonw_start_object(json_wtr);
+ if (func_sig[0] != '\0') {
+ jsonw_name(json_wtr, "proto");
+ jsonw_string(json_wtr, func_sig);
+ }
jsonw_name(json_wtr, "name");
jsonw_string(json_wtr, sym_name);
jsonw_name(json_wtr, "insns");
} else {
+ if (func_sig[0] != '\0')
+ printf("%s:\n", func_sig);
printf("%s:\n", sym_name);
}
@@ -685,12 +737,14 @@ static int do_dump(int argc, char **argv)
free(buf);
free(func_ksyms);
free(func_lens);
+ free(func_types);
return 0;
err_free:
free(buf);
free(func_ksyms);
free(func_lens);
+ free(func_types);
return -1;
}
--
2.17.1
^ permalink raw reply related
* [PATCH bpf-next v2 12/13] tools/bpf: enhance test_btf file testing to test func info
From: Yonghong Song @ 2018-10-17 7:23 UTC (permalink / raw)
To: ast, kafai, daniel, netdev; +Cc: kernel-team
In-Reply-To: <20181017072400.2768484-1-yhs@fb.com>
Change the bpf programs test_btf_haskv.c and test_btf_nokv.c to
have two sections, and enhance test_btf.c test_file feature
to test btf func_info returned by the kernel.
Signed-off-by: Yonghong Song <yhs@fb.com>
---
tools/testing/selftests/bpf/test_btf.c | 72 +++++++++++++++++++-
tools/testing/selftests/bpf/test_btf_haskv.c | 16 ++++-
tools/testing/selftests/bpf/test_btf_nokv.c | 16 ++++-
3 files changed, 99 insertions(+), 5 deletions(-)
diff --git a/tools/testing/selftests/bpf/test_btf.c b/tools/testing/selftests/bpf/test_btf.c
index e03a8cea4bb7..0bbefb571426 100644
--- a/tools/testing/selftests/bpf/test_btf.c
+++ b/tools/testing/selftests/bpf/test_btf.c
@@ -2235,10 +2235,16 @@ static int file_has_btf_elf(const char *fn)
static int do_test_file(unsigned int test_num)
{
const struct btf_file_test *test = &file_tests[test_num - 1];
+ const char *expected_fnames[] = {"_dummy_tracepoint",
+ "test_long_fname_1",
+ "test_long_fname_2"};
+ __u32 func_lens[10], func_types[10], info_len;
+ struct bpf_prog_info info = {};
struct bpf_object *obj = NULL;
struct bpf_program *prog;
+ struct btf *btf = NULL;
struct bpf_map *map;
- int err;
+ int i, err, prog_fd;
fprintf(stderr, "BTF libbpf test[%u] (%s): ", test_num,
test->file);
@@ -2271,6 +2277,7 @@ static int do_test_file(unsigned int test_num)
err = bpf_object__load(obj);
if (CHECK(err < 0, "bpf_object__load: %d", err))
goto done;
+ prog_fd = bpf_program__fd(prog);
map = bpf_object__find_map_by_name(obj, "btf_map");
if (CHECK(!map, "btf_map not found")) {
@@ -2285,6 +2292,69 @@ static int do_test_file(unsigned int test_num)
test->btf_kv_notfound))
goto done;
+ if (!jit_enabled)
+ goto skip_jit;
+
+ info_len = sizeof(struct bpf_prog_info);
+ info.nr_jited_func_types = ARRAY_SIZE(func_types);
+ info.nr_jited_func_lens = ARRAY_SIZE(func_lens);
+ info.jited_func_types = ptr_to_u64(&func_types[0]);
+ info.jited_func_lens = ptr_to_u64(&func_lens[0]);
+
+ err = bpf_obj_get_info_by_fd(prog_fd, &info, &info_len);
+
+ if (CHECK(err == -1, "invalid get info errno:%d", errno)) {
+ fprintf(stderr, "%s\n", btf_log_buf);
+ err = -1;
+ goto done;
+ }
+ if (CHECK(info.nr_jited_func_lens != 3,
+ "incorrect info.nr_jited_func_lens %d",
+ info.nr_jited_func_lens)) {
+ err = -1;
+ goto done;
+ }
+ if (CHECK(info.nr_jited_func_types != 3,
+ "incorrect info.nr_jited_func_types %d",
+ info.nr_jited_func_types)) {
+ err = -1;
+ goto done;
+ }
+ if (CHECK(info.btf_id == 0, "incorrect btf_id = 0")) {
+ err = -1;
+ goto done;
+ }
+
+ err = btf_get_from_id(info.btf_id, &btf);
+ if (CHECK(err, "cannot get btf from kernel, err: %d", err))
+ goto done;
+
+ /* check three functions */
+ for (i = 0; i < 3; i++) {
+ const struct btf_type *t;
+ const char *fname;
+
+ t = btf__type_by_id(btf, func_types[i]);
+ if (CHECK(!t, "btf__type_by_id failure: id %u",
+ func_types[i])) {
+ err = -1;
+ goto done;
+ }
+
+ fname = btf__name_by_offset(btf, t->name_off);
+ err = strcmp(fname, expected_fnames[i]);
+ /* for the second and third functions in .text section,
+ * the compiler may order them either way.
+ */
+ if (i && err)
+ err = strcmp(fname, expected_fnames[3 - i]);
+ if (CHECK(err, "incorrect fname %s", fname ? : "")) {
+ err = -1;
+ goto done;
+ }
+ }
+
+skip_jit:
fprintf(stderr, "OK");
done:
diff --git a/tools/testing/selftests/bpf/test_btf_haskv.c b/tools/testing/selftests/bpf/test_btf_haskv.c
index b21b876f475d..e5c79fe0ffdb 100644
--- a/tools/testing/selftests/bpf/test_btf_haskv.c
+++ b/tools/testing/selftests/bpf/test_btf_haskv.c
@@ -24,8 +24,8 @@ struct dummy_tracepoint_args {
struct sock *sock;
};
-SEC("dummy_tracepoint")
-int _dummy_tracepoint(struct dummy_tracepoint_args *arg)
+__attribute__((noinline))
+static int test_long_fname_2(struct dummy_tracepoint_args *arg)
{
struct ipv_counts *counts;
int key = 0;
@@ -42,4 +42,16 @@ int _dummy_tracepoint(struct dummy_tracepoint_args *arg)
return 0;
}
+__attribute__((noinline))
+static int test_long_fname_1(struct dummy_tracepoint_args *arg)
+{
+ return test_long_fname_2(arg);
+}
+
+SEC("dummy_tracepoint")
+int _dummy_tracepoint(struct dummy_tracepoint_args *arg)
+{
+ return test_long_fname_1(arg);
+}
+
char _license[] SEC("license") = "GPL";
diff --git a/tools/testing/selftests/bpf/test_btf_nokv.c b/tools/testing/selftests/bpf/test_btf_nokv.c
index 0ed8e088eebf..434188c37774 100644
--- a/tools/testing/selftests/bpf/test_btf_nokv.c
+++ b/tools/testing/selftests/bpf/test_btf_nokv.c
@@ -22,8 +22,8 @@ struct dummy_tracepoint_args {
struct sock *sock;
};
-SEC("dummy_tracepoint")
-int _dummy_tracepoint(struct dummy_tracepoint_args *arg)
+__attribute__((noinline))
+static int test_long_fname_2(struct dummy_tracepoint_args *arg)
{
struct ipv_counts *counts;
int key = 0;
@@ -40,4 +40,16 @@ int _dummy_tracepoint(struct dummy_tracepoint_args *arg)
return 0;
}
+__attribute__((noinline))
+static int test_long_fname_1(struct dummy_tracepoint_args *arg)
+{
+ return test_long_fname_2(arg);
+}
+
+SEC("dummy_tracepoint")
+int _dummy_tracepoint(struct dummy_tracepoint_args *arg)
+{
+ return test_long_fname_1(arg);
+}
+
char _license[] SEC("license") = "GPL";
--
2.17.1
^ permalink raw reply related
* [PATCH bpf-next v2 10/13] tools/bpf: do not use pahole if clang/llvm can generate BTF sections
From: Yonghong Song @ 2018-10-17 7:23 UTC (permalink / raw)
To: ast, kafai, daniel, netdev; +Cc: kernel-team
Add additional checks in tools/testing/selftests/bpf and
samples/bpf such that if clang/llvm compiler can generate
BTF sections, do not use pahole.
Signed-off-by: Yonghong Song <yhs@fb.com>
---
samples/bpf/Makefile | 8 ++++++++
tools/testing/selftests/bpf/Makefile | 8 ++++++++
2 files changed, 16 insertions(+)
diff --git a/samples/bpf/Makefile b/samples/bpf/Makefile
index be0a961450bc..870fe7ee2b69 100644
--- a/samples/bpf/Makefile
+++ b/samples/bpf/Makefile
@@ -208,12 +208,20 @@ endif
BTF_LLC_PROBE := $(shell $(LLC) -march=bpf -mattr=help 2>&1 | grep dwarfris)
BTF_PAHOLE_PROBE := $(shell $(BTF_PAHOLE) --help 2>&1 | grep BTF)
BTF_OBJCOPY_PROBE := $(shell $(LLVM_OBJCOPY) --help 2>&1 | grep -i 'usage.*llvm')
+BTF_LLVM_PROBE := $(shell echo "int main() { return 0; }" | \
+ clang -target bpf -O2 -g -c -x c - -o ./llvm_btf_verify.o; \
+ readelf -S ./llvm_btf_verify.o | grep BTF; \
+ /bin/rm -f ./llvm_btf_verify.o)
+ifneq ($(BTF_LLVM_PROBE),)
+ EXTRA_CFLAGS += -g
+else
ifneq ($(and $(BTF_LLC_PROBE),$(BTF_PAHOLE_PROBE),$(BTF_OBJCOPY_PROBE)),)
EXTRA_CFLAGS += -g
LLC_FLAGS += -mattr=dwarfris
DWARF2BTF = y
endif
+endif
# Trick to allow make to be run from this directory
all:
diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile
index d99dd6fc3fbe..8d5612724db8 100644
--- a/tools/testing/selftests/bpf/Makefile
+++ b/tools/testing/selftests/bpf/Makefile
@@ -121,7 +121,14 @@ $(OUTPUT)/test_xdp_noinline.o: CLANG_FLAGS += -fno-inline
BTF_LLC_PROBE := $(shell $(LLC) -march=bpf -mattr=help 2>&1 | grep dwarfris)
BTF_PAHOLE_PROBE := $(shell $(BTF_PAHOLE) --help 2>&1 | grep BTF)
BTF_OBJCOPY_PROBE := $(shell $(LLVM_OBJCOPY) --help 2>&1 | grep -i 'usage.*llvm')
+BTF_LLVM_PROBE := $(shell echo "int main() { return 0; }" | \
+ clang -target bpf -O2 -g -c -x c - -o ./llvm_btf_verify.o; \
+ readelf -S ./llvm_btf_verify.o | grep BTF; \
+ /bin/rm -f ./llvm_btf_verify.o)
+ifneq ($(BTF_LLVM_PROBE),)
+ CLANG_FLAGS += -g
+else
ifneq ($(BTF_LLC_PROBE),)
ifneq ($(BTF_PAHOLE_PROBE),)
ifneq ($(BTF_OBJCOPY_PROBE),)
@@ -131,6 +138,7 @@ ifneq ($(BTF_OBJCOPY_PROBE),)
endif
endif
endif
+endif
$(OUTPUT)/%.o: %.c
$(CLANG) $(CLANG_FLAGS) \
--
2.17.1
^ permalink raw reply related
* SMSC9730 Autosuspend/Resume Questions
From: Frieder Schrempf @ 2018-10-17 15:21 UTC (permalink / raw)
To: Steve Glendinning, Microchip Linux Driver Support,
David S. Miller, netdev
Cc: Oliver Neukum, linux-usb, linux-kernel
Hi,
I recently tested a board with SMSC9730 connected via USB HSIC to an
i.MX6S SOC. I used these patches on top of v4.14-rc8 for the USB HSIC
support: [1].
When I turned on autosuspend, the smsc95xx stopped in the middle of the
suspending routine and
/sys/bus/usb/devices/usb3/3-1/power/runtime_status reported "suspending"
forever.
With some debug logs I found out, that the last line of code that was
executed is [2], after that I didn't get any further messages.
Then I applied the following diff and the suspend/resume started to work
reliably:
@@ -1382,10 +1385,11 @@ static int smsc95xx_link_ok_nopm(struct usbnet *dev)
ret = smsc95xx_mdio_read_nopm(dev->net, mii->phy_id, MII_BMSR);
if (ret < 0)
return ret;
-
+ /*
ret = smsc95xx_mdio_read_nopm(dev->net, mii->phy_id, MII_BMSR);
if (ret < 0)
return ret;
+ */
return !!(ret & BMSR_LSTATUS);
}
So it seems like the dummy read, that is commented with "first, a dummy
read, needed to latch some MII phys" causes problems in my setup. Do you
have an idea what could be the reason? Is this a proper fix?
Thanks,
Frieder
[1] https://patchwork.kernel.org/cover/10643089/
[2]
https://github.com/torvalds/linux/blob/bab5c80b211035739997ebd361a679fa85b39465/drivers/net/usb/smsc95xx.c#L1382
^ permalink raw reply
* Re: [RFC PATCH 02/11] dt-bindings: phy: add cpsw port interface mode selection phy bindings
From: Rob Herring @ 2018-10-17 15:39 UTC (permalink / raw)
To: Grygorii Strashko
Cc: Tony Lindgren, David S. Miller, netdev, Kishon Vijay Abraham I,
Sekhar Nori, linux-kernel, linux-omap, devicetree
In-Reply-To: <3fa09831-0f70-dfcc-3fd9-f877215a4631@ti.com>
On Tue, Oct 09, 2018 at 03:10:34PM -0500, Grygorii Strashko wrote:
>
>
> On 10/09/2018 09:40 AM, Tony Lindgren wrote:
> > * Grygorii Strashko <grygorii.strashko@ti.com> [181008 23:54]:
> >> +Examples:
> >> + phy_gmii_sel: phy-gmii-sel {
> >> + compatible = "ti,am3352-phy-gmii-sel";
> >> + syscon-scm = <&scm_conf>;
> >> + #phy-cells = <2>;
> >> + };
> >
> > Now that this driver can live in it's proper place in the
>
> right
>
> > dts, you may want to consider just using standard reg
> > property for it instead of the syscon-scm. And also get
> > rid of the syscon reads and writes.
>
> Could you help clarify how to get syscon in this case?
> syscon_node_to_regmap(dev->parent->of_node)?
>
> Also, there are could be more then one gmii_sel registers in SCM in the future,
> so I hidden offsets in of_match data.
> As result, "reg" not needed at all now.
If there's a defined register range which doesn't overlap with other
things (other than the parent), then use reg whether you currently need
it or not.
Rob
^ permalink raw reply
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