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* [PATCH v2 0/4] forbid fix {SQ,IO}POLL
@ 2020-06-03 13:29 Pavel Begunkov
  2020-06-03 13:29 ` [PATCH v2 1/4] io_uring: fix {SQ,IO}POLL with unsupported opcodes Pavel Begunkov
                   ` (4 more replies)
  0 siblings, 5 replies; 6+ messages in thread
From: Pavel Begunkov @ 2020-06-03 13:29 UTC (permalink / raw)
  To: Jens Axboe, io-uring, linux-kernel

The first one adds checks {SQPOLL,IOPOLL}. IOPOLL check can be
moved in the common path later, or rethinked entirely, e.g.
not io_iopoll_req_issued()'ed for unsupported opcodes.

3 others are just cleanups on top.


v2: add IOPOLL to the whole bunch of opcodes in [1/4].
    dirty and effective.

Pavel Begunkov (4):
  io_uring: fix {SQ,IO}POLL with unsupported opcodes
  io_uring: do build_open_how() only once
  io_uring: deduplicate io_openat{,2}_prep()
  io_uring: move send/recv IOPOLL check into prep

 fs/io_uring.c | 94 ++++++++++++++++++++++++++-------------------------
 1 file changed, 48 insertions(+), 46 deletions(-)

-- 
2.24.0


^ permalink raw reply	[flat|nested] 6+ messages in thread

* [PATCH v2 1/4] io_uring: fix {SQ,IO}POLL with unsupported opcodes
  2020-06-03 13:29 [PATCH v2 0/4] forbid fix {SQ,IO}POLL Pavel Begunkov
@ 2020-06-03 13:29 ` Pavel Begunkov
  2020-06-03 13:29 ` [PATCH v2 2/4] io_uring: do build_open_how() only once Pavel Begunkov
                   ` (3 subsequent siblings)
  4 siblings, 0 replies; 6+ messages in thread
From: Pavel Begunkov @ 2020-06-03 13:29 UTC (permalink / raw)
  To: Jens Axboe, io-uring, linux-kernel

IORING_SETUP_IOPOLL is defined only for read/write, other opcodes should
be disallowed, otherwise it'll get an error as below. Also refuse
open/cloes with SQPOLL, as the polling thread wouldn't know which file
table to use.

RIP: 0010:io_iopoll_getevents+0x111/0x5a0
Call Trace:
 ? _raw_spin_unlock_irqrestore+0x24/0x40
 ? do_send_sig_info+0x64/0x90
 io_iopoll_reap_events.part.0+0x5e/0xa0
 io_ring_ctx_wait_and_kill+0x132/0x1c0
 io_uring_release+0x20/0x30
 __fput+0xcd/0x230
 ____fput+0xe/0x10
 task_work_run+0x67/0xa0
 do_exit+0x353/0xb10
 ? handle_mm_fault+0xd4/0x200
 ? syscall_trace_enter+0x18c/0x2c0
 do_group_exit+0x43/0xa0
 __x64_sys_exit_group+0x18/0x20
 do_syscall_64+0x60/0x1e0
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
---
 fs/io_uring.c | 24 ++++++++++++++++++++++++
 1 file changed, 24 insertions(+)

diff --git a/fs/io_uring.c b/fs/io_uring.c
index 732ec73ec3c0..2463aaca3172 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -2765,6 +2765,8 @@ static int __io_splice_prep(struct io_kiocb *req,
 
 	if (req->flags & REQ_F_NEED_CLEANUP)
 		return 0;
+	if (unlikely(ctx->flags & IORING_SETUP_IOPOLL))
+		return -EINVAL;
 
 	sp->file_in = NULL;
 	sp->len = READ_ONCE(sqe->len);
@@ -2965,6 +2967,8 @@ static int io_fallocate_prep(struct io_kiocb *req,
 {
 	if (sqe->ioprio || sqe->buf_index || sqe->rw_flags)
 		return -EINVAL;
+	if (unlikely(ctx->flags & IORING_SETUP_IOPOLL))
+		return -EINVAL;
 
 	req->sync.off = READ_ONCE(sqe->off);
 	req->sync.len = READ_ONCE(sqe->addr);
@@ -2990,6 +2994,8 @@ static int io_openat_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
 	const char __user *fname;
 	int ret;
 
+	if (unlikely(req->ctx->flags & (IORING_SETUP_IOPOLL|IORING_SETUP_SQPOLL)))
+		return -EINVAL;
 	if (sqe->ioprio || sqe->buf_index)
 		return -EINVAL;
 	if (req->flags & REQ_F_FIXED_FILE)
@@ -3023,6 +3029,8 @@ static int io_openat2_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
 	size_t len;
 	int ret;
 
+	if (unlikely(req->ctx->flags & (IORING_SETUP_IOPOLL|IORING_SETUP_SQPOLL)))
+		return -EINVAL;
 	if (sqe->ioprio || sqe->buf_index)
 		return -EINVAL;
 	if (req->flags & REQ_F_FIXED_FILE)
@@ -3107,6 +3115,8 @@ static int io_remove_buffers_prep(struct io_kiocb *req,
 
 	if (sqe->ioprio || sqe->rw_flags || sqe->addr || sqe->len || sqe->off)
 		return -EINVAL;
+	if (unlikely(ctx->flags & IORING_SETUP_IOPOLL))
+		return -EINVAL;
 
 	tmp = READ_ONCE(sqe->fd);
 	if (!tmp || tmp > USHRT_MAX)
@@ -3174,6 +3184,8 @@ static int io_provide_buffers_prep(struct io_kiocb *req,
 	struct io_provide_buf *p = &req->pbuf;
 	u64 tmp;
 
+	if (unlikely(ctx->flags & IORING_SETUP_IOPOLL))
+		return -EINVAL;
 	if (sqe->ioprio || sqe->rw_flags)
 		return -EINVAL;
 
@@ -3262,6 +3274,8 @@ static int io_epoll_ctl_prep(struct io_kiocb *req,
 #if defined(CONFIG_EPOLL)
 	if (sqe->ioprio || sqe->buf_index)
 		return -EINVAL;
+	if (unlikely(ctx->flags & IORING_SETUP_IOPOLL))
+		return -EINVAL;
 
 	req->epoll.epfd = READ_ONCE(sqe->fd);
 	req->epoll.op = READ_ONCE(sqe->len);
@@ -3306,6 +3320,8 @@ static int io_madvise_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
 #if defined(CONFIG_ADVISE_SYSCALLS) && defined(CONFIG_MMU)
 	if (sqe->ioprio || sqe->buf_index || sqe->off)
 		return -EINVAL;
+	if (unlikely(ctx->flags & IORING_SETUP_IOPOLL))
+		return -EINVAL;
 
 	req->madvise.addr = READ_ONCE(sqe->addr);
 	req->madvise.len = READ_ONCE(sqe->len);
@@ -3340,6 +3356,8 @@ static int io_fadvise_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
 {
 	if (sqe->ioprio || sqe->buf_index || sqe->addr)
 		return -EINVAL;
+	if (unlikely(ctx->flags & IORING_SETUP_IOPOLL))
+		return -EINVAL;
 
 	req->fadvise.offset = READ_ONCE(sqe->off);
 	req->fadvise.len = READ_ONCE(sqe->len);
@@ -3373,6 +3391,8 @@ static int io_fadvise(struct io_kiocb *req, bool force_nonblock)
 
 static int io_statx_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
 {
+	if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
+		return -EINVAL;
 	if (sqe->ioprio || sqe->buf_index)
 		return -EINVAL;
 	if (req->flags & REQ_F_FIXED_FILE)
@@ -3417,6 +3437,8 @@ static int io_close_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
 	 */
 	req->work.flags |= IO_WQ_WORK_NO_CANCEL;
 
+	if (unlikely(req->ctx->flags & (IORING_SETUP_IOPOLL|IORING_SETUP_SQPOLL)))
+		return -EINVAL;
 	if (sqe->ioprio || sqe->off || sqe->addr || sqe->len ||
 	    sqe->rw_flags || sqe->buf_index)
 		return -EINVAL;
@@ -4906,6 +4928,8 @@ static int io_files_update_prep(struct io_kiocb *req,
 {
 	if (sqe->flags || sqe->ioprio || sqe->rw_flags)
 		return -EINVAL;
+	if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
+		return -EINVAL;
 
 	req->files_update.offset = READ_ONCE(sqe->off);
 	req->files_update.nr_args = READ_ONCE(sqe->len);
-- 
2.24.0


^ permalink raw reply related	[flat|nested] 6+ messages in thread

* [PATCH v2 2/4] io_uring: do build_open_how() only once
  2020-06-03 13:29 [PATCH v2 0/4] forbid fix {SQ,IO}POLL Pavel Begunkov
  2020-06-03 13:29 ` [PATCH v2 1/4] io_uring: fix {SQ,IO}POLL with unsupported opcodes Pavel Begunkov
@ 2020-06-03 13:29 ` Pavel Begunkov
  2020-06-03 13:29 ` [PATCH v2 3/4] io_uring: deduplicate io_openat{,2}_prep() Pavel Begunkov
                   ` (2 subsequent siblings)
  4 siblings, 0 replies; 6+ messages in thread
From: Pavel Begunkov @ 2020-06-03 13:29 UTC (permalink / raw)
  To: Jens Axboe, io-uring, linux-kernel

build_open_how() is just adjusting open_flags/mode. Do it once during
prep. It looks better than storing raw values for the future.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
---
 fs/io_uring.c | 13 +++++++------
 1 file changed, 7 insertions(+), 6 deletions(-)

diff --git a/fs/io_uring.c b/fs/io_uring.c
index 2463aaca3172..75ff635bb30e 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -2992,6 +2992,7 @@ static int io_fallocate(struct io_kiocb *req, bool force_nonblock)
 static int io_openat_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
 {
 	const char __user *fname;
+	u64 flags, mode;
 	int ret;
 
 	if (unlikely(req->ctx->flags & (IORING_SETUP_IOPOLL|IORING_SETUP_SQPOLL)))
@@ -3003,13 +3004,14 @@ static int io_openat_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
 	if (req->flags & REQ_F_NEED_CLEANUP)
 		return 0;
 
-	req->open.dfd = READ_ONCE(sqe->fd);
-	req->open.how.mode = READ_ONCE(sqe->len);
-	fname = u64_to_user_ptr(READ_ONCE(sqe->addr));
-	req->open.how.flags = READ_ONCE(sqe->open_flags);
+	mode = READ_ONCE(sqe->len);
+	flags = READ_ONCE(sqe->open_flags);
 	if (force_o_largefile())
-		req->open.how.flags |= O_LARGEFILE;
+		flags |= O_LARGEFILE;
+	req->open.how = build_open_how(flags, mode);
 
+	req->open.dfd = READ_ONCE(sqe->fd);
+	fname = u64_to_user_ptr(READ_ONCE(sqe->addr));
 	req->open.filename = getname(fname);
 	if (IS_ERR(req->open.filename)) {
 		ret = PTR_ERR(req->open.filename);
@@ -3103,7 +3105,6 @@ static int io_openat2(struct io_kiocb *req, bool force_nonblock)
 
 static int io_openat(struct io_kiocb *req, bool force_nonblock)
 {
-	req->open.how = build_open_how(req->open.how.flags, req->open.how.mode);
 	return io_openat2(req, force_nonblock);
 }
 
-- 
2.24.0


^ permalink raw reply related	[flat|nested] 6+ messages in thread

* [PATCH v2 3/4] io_uring: deduplicate io_openat{,2}_prep()
  2020-06-03 13:29 [PATCH v2 0/4] forbid fix {SQ,IO}POLL Pavel Begunkov
  2020-06-03 13:29 ` [PATCH v2 1/4] io_uring: fix {SQ,IO}POLL with unsupported opcodes Pavel Begunkov
  2020-06-03 13:29 ` [PATCH v2 2/4] io_uring: do build_open_how() only once Pavel Begunkov
@ 2020-06-03 13:29 ` Pavel Begunkov
  2020-06-03 13:29 ` [PATCH v2 4/4] io_uring: move send/recv IOPOLL check into prep Pavel Begunkov
  2020-06-03 14:54 ` [PATCH v2 0/4] forbid fix {SQ,IO}POLL Pavel Begunkov
  4 siblings, 0 replies; 6+ messages in thread
From: Pavel Begunkov @ 2020-06-03 13:29 UTC (permalink / raw)
  To: Jens Axboe, io-uring, linux-kernel

io_openat_prep() and io_openat2_prep() are identical except for how
struct open_how is built. Deduplicate it with a helper.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
---
 fs/io_uring.c | 55 ++++++++++++++++++---------------------------------
 1 file changed, 19 insertions(+), 36 deletions(-)

diff --git a/fs/io_uring.c b/fs/io_uring.c
index 75ff635bb30e..7d49bcba859c 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -2989,26 +2989,21 @@ static int io_fallocate(struct io_kiocb *req, bool force_nonblock)
 	return 0;
 }
 
-static int io_openat_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
+static int __io_openat_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
 {
 	const char __user *fname;
-	u64 flags, mode;
 	int ret;
 
 	if (unlikely(req->ctx->flags & (IORING_SETUP_IOPOLL|IORING_SETUP_SQPOLL)))
 		return -EINVAL;
-	if (sqe->ioprio || sqe->buf_index)
+	if (unlikely(sqe->ioprio || sqe->buf_index))
 		return -EINVAL;
-	if (req->flags & REQ_F_FIXED_FILE)
+	if (unlikely(req->flags & REQ_F_FIXED_FILE))
 		return -EBADF;
-	if (req->flags & REQ_F_NEED_CLEANUP)
-		return 0;
 
-	mode = READ_ONCE(sqe->len);
-	flags = READ_ONCE(sqe->open_flags);
-	if (force_o_largefile())
-		flags |= O_LARGEFILE;
-	req->open.how = build_open_how(flags, mode);
+	/* open.how should be already initialised */
+	if (!(req->open.how.flags & O_PATH) && force_o_largefile())
+		req->open.how.flags |= O_LARGEFILE;
 
 	req->open.dfd = READ_ONCE(sqe->fd);
 	fname = u64_to_user_ptr(READ_ONCE(sqe->addr));
@@ -3018,33 +3013,33 @@ static int io_openat_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
 		req->open.filename = NULL;
 		return ret;
 	}
-
 	req->open.nofile = rlimit(RLIMIT_NOFILE);
 	req->flags |= REQ_F_NEED_CLEANUP;
 	return 0;
 }
 
+static int io_openat_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
+{
+	u64 flags, mode;
+
+	if (req->flags & REQ_F_NEED_CLEANUP)
+		return 0;
+	mode = READ_ONCE(sqe->len);
+	flags = READ_ONCE(sqe->open_flags);
+	req->open.how = build_open_how(flags, mode);
+	return __io_openat_prep(req, sqe);
+}
+
 static int io_openat2_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
 {
 	struct open_how __user *how;
-	const char __user *fname;
 	size_t len;
 	int ret;
 
-	if (unlikely(req->ctx->flags & (IORING_SETUP_IOPOLL|IORING_SETUP_SQPOLL)))
-		return -EINVAL;
-	if (sqe->ioprio || sqe->buf_index)
-		return -EINVAL;
-	if (req->flags & REQ_F_FIXED_FILE)
-		return -EBADF;
 	if (req->flags & REQ_F_NEED_CLEANUP)
 		return 0;
-
-	req->open.dfd = READ_ONCE(sqe->fd);
-	fname = u64_to_user_ptr(READ_ONCE(sqe->addr));
 	how = u64_to_user_ptr(READ_ONCE(sqe->addr2));
 	len = READ_ONCE(sqe->len);
-
 	if (len < OPEN_HOW_SIZE_VER0)
 		return -EINVAL;
 
@@ -3053,19 +3048,7 @@ static int io_openat2_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
 	if (ret)
 		return ret;
 
-	if (!(req->open.how.flags & O_PATH) && force_o_largefile())
-		req->open.how.flags |= O_LARGEFILE;
-
-	req->open.filename = getname(fname);
-	if (IS_ERR(req->open.filename)) {
-		ret = PTR_ERR(req->open.filename);
-		req->open.filename = NULL;
-		return ret;
-	}
-
-	req->open.nofile = rlimit(RLIMIT_NOFILE);
-	req->flags |= REQ_F_NEED_CLEANUP;
-	return 0;
+	return __io_openat_prep(req, sqe);
 }
 
 static int io_openat2(struct io_kiocb *req, bool force_nonblock)
-- 
2.24.0


^ permalink raw reply related	[flat|nested] 6+ messages in thread

* [PATCH v2 4/4] io_uring: move send/recv IOPOLL check into prep
  2020-06-03 13:29 [PATCH v2 0/4] forbid fix {SQ,IO}POLL Pavel Begunkov
                   ` (2 preceding siblings ...)
  2020-06-03 13:29 ` [PATCH v2 3/4] io_uring: deduplicate io_openat{,2}_prep() Pavel Begunkov
@ 2020-06-03 13:29 ` Pavel Begunkov
  2020-06-03 14:54 ` [PATCH v2 0/4] forbid fix {SQ,IO}POLL Pavel Begunkov
  4 siblings, 0 replies; 6+ messages in thread
From: Pavel Begunkov @ 2020-06-03 13:29 UTC (permalink / raw)
  To: Jens Axboe, io-uring, linux-kernel

Fail recv/send in case of IORING_SETUP_IOPOLL earlier during prep,
so it'd be done only once. Removes duplication as well

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
---
 fs/io_uring.c | 18 ++++++------------
 1 file changed, 6 insertions(+), 12 deletions(-)

diff --git a/fs/io_uring.c b/fs/io_uring.c
index 7d49bcba859c..d63a13d10de0 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -3555,6 +3555,9 @@ static int io_sendmsg_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
 	struct io_async_ctx *io = req->io;
 	int ret;
 
+	if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
+		return -EINVAL;
+
 	sr->msg_flags = READ_ONCE(sqe->msg_flags);
 	sr->msg = u64_to_user_ptr(READ_ONCE(sqe->addr));
 	sr->len = READ_ONCE(sqe->len);
@@ -3584,9 +3587,6 @@ static int io_sendmsg(struct io_kiocb *req, bool force_nonblock)
 	struct socket *sock;
 	int ret;
 
-	if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
-		return -EINVAL;
-
 	sock = sock_from_file(req->file, &ret);
 	if (sock) {
 		struct io_async_ctx io;
@@ -3640,9 +3640,6 @@ static int io_send(struct io_kiocb *req, bool force_nonblock)
 	struct socket *sock;
 	int ret;
 
-	if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
-		return -EINVAL;
-
 	sock = sock_from_file(req->file, &ret);
 	if (sock) {
 		struct io_sr_msg *sr = &req->sr_msg;
@@ -3795,6 +3792,9 @@ static int io_recvmsg_prep(struct io_kiocb *req,
 	struct io_async_ctx *io = req->io;
 	int ret;
 
+	if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
+		return -EINVAL;
+
 	sr->msg_flags = READ_ONCE(sqe->msg_flags);
 	sr->msg = u64_to_user_ptr(READ_ONCE(sqe->addr));
 	sr->len = READ_ONCE(sqe->len);
@@ -3823,9 +3823,6 @@ static int io_recvmsg(struct io_kiocb *req, bool force_nonblock)
 	struct socket *sock;
 	int ret, cflags = 0;
 
-	if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
-		return -EINVAL;
-
 	sock = sock_from_file(req->file, &ret);
 	if (sock) {
 		struct io_buffer *kbuf;
@@ -3887,9 +3884,6 @@ static int io_recv(struct io_kiocb *req, bool force_nonblock)
 	struct socket *sock;
 	int ret, cflags = 0;
 
-	if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
-		return -EINVAL;
-
 	sock = sock_from_file(req->file, &ret);
 	if (sock) {
 		struct io_sr_msg *sr = &req->sr_msg;
-- 
2.24.0


^ permalink raw reply related	[flat|nested] 6+ messages in thread

* Re: [PATCH v2 0/4] forbid fix {SQ,IO}POLL
  2020-06-03 13:29 [PATCH v2 0/4] forbid fix {SQ,IO}POLL Pavel Begunkov
                   ` (3 preceding siblings ...)
  2020-06-03 13:29 ` [PATCH v2 4/4] io_uring: move send/recv IOPOLL check into prep Pavel Begunkov
@ 2020-06-03 14:54 ` Pavel Begunkov
  4 siblings, 0 replies; 6+ messages in thread
From: Pavel Begunkov @ 2020-06-03 14:54 UTC (permalink / raw)
  To: Jens Axboe, io-uring, linux-kernel

Something went wrong, don't mind it

On 03/06/2020 16:29, Pavel Begunkov wrote:
> The first one adds checks {SQPOLL,IOPOLL}. IOPOLL check can be
> moved in the common path later, or rethinked entirely, e.g.
> not io_iopoll_req_issued()'ed for unsupported opcodes.
> 
> 3 others are just cleanups on top.
> 
> 
> v2: add IOPOLL to the whole bunch of opcodes in [1/4].
>     dirty and effective.
> 
> Pavel Begunkov (4):
>   io_uring: fix {SQ,IO}POLL with unsupported opcodes
>   io_uring: do build_open_how() only once
>   io_uring: deduplicate io_openat{,2}_prep()
>   io_uring: move send/recv IOPOLL check into prep
> 
>  fs/io_uring.c | 94 ++++++++++++++++++++++++++-------------------------
>  1 file changed, 48 insertions(+), 46 deletions(-)
> 

-- 
Pavel Begunkov

^ permalink raw reply	[flat|nested] 6+ messages in thread

end of thread, other threads:[~2020-06-03 14:55 UTC | newest]

Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2020-06-03 13:29 [PATCH v2 0/4] forbid fix {SQ,IO}POLL Pavel Begunkov
2020-06-03 13:29 ` [PATCH v2 1/4] io_uring: fix {SQ,IO}POLL with unsupported opcodes Pavel Begunkov
2020-06-03 13:29 ` [PATCH v2 2/4] io_uring: do build_open_how() only once Pavel Begunkov
2020-06-03 13:29 ` [PATCH v2 3/4] io_uring: deduplicate io_openat{,2}_prep() Pavel Begunkov
2020-06-03 13:29 ` [PATCH v2 4/4] io_uring: move send/recv IOPOLL check into prep Pavel Begunkov
2020-06-03 14:54 ` [PATCH v2 0/4] forbid fix {SQ,IO}POLL Pavel Begunkov

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