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205 Commits

Author SHA1 Message Date
Linus Torvalds 5bd4af34a0 TTY/Serial patches for 4.20-rc1
Here is the big tty and serial pull request for 4.20-rc1
 
 Lots of little things here, including a merge from the SPI tree in order
 to keep things simpler for everyone to sync around for one platform.
 
 Major stuff is:
 	- tty buffer clearing after use
 	- atmel_serial fixes and additions
 	- xilinx uart driver updates
 and of course, lots of tiny fixes and additions to individual serial
 drivers.
 
 All of these have been in linux-next with no reported issues for a
 while.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
 -----BEGIN PGP SIGNATURE-----
 
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 aC5jb20ACgkQMUfUDdst+ymYhgCfbxr0T+4lF/rpGxNXNnV4u5boRJUAn2L8R+1y
 URbAWHvKfaby2AVfQ1z0
 =qTHH
 -----END PGP SIGNATURE-----

Merge tag 'tty-4.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty/serial updates from Greg KH:
 "Here is the big tty and serial pull request for 4.20-rc1

  Lots of little things here, including a merge from the SPI tree in
  order to keep things simpler for everyone to sync around for one
  platform.

  Major stuff is:

   - tty buffer clearing after use

   - atmel_serial fixes and additions

   - xilinx uart driver updates

  and of course, lots of tiny fixes and additions to individual serial
  drivers.

  All of these have been in linux-next with no reported issues for a
  while"

* tag 'tty-4.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (66 commits)
  of: base: Change logic in of_alias_get_alias_list()
  of: base: Fix english spelling in of_alias_get_alias_list()
  serial: sh-sci: do not warn if DMA transfers are not supported
  serial: uartps: Do not allow use aliases >= MAX_UART_INSTANCES
  tty: check name length in tty_find_polling_driver()
  serial: sh-sci: Add r8a77990 support
  tty: wipe buffer if not echoing data
  tty: wipe buffer.
  serial: fsl_lpuart: Remove the alias node dependence
  TTY: sn_console: Replace spin_is_locked() with spin_trylock()
  Revert "serial:serial_core: Allow use of CTS for PPS line discipline"
  serial: 8250_uniphier: add auto-flow-control support
  serial: 8250_uniphier: flatten probe function
  serial: 8250_uniphier: remove unused "fifo-size" property
  dt-bindings: serial: sh-sci: Document r8a7744 bindings
  serial: uartps: Fix missing unlock on error in cdns_get_id()
  tty/serial: atmel: add ISO7816 support
  tty/serial_core: add ISO7816 infrastructure
  serial:serial_core: Allow use of CTS for PPS line discipline
  serial: docs: Fix filename for serial reference implementation
  ...
2018-10-29 10:42:20 -07:00
Al Viro 7ee3296551 kill TIOCSER[SG]WILD
the only user is very old setserial rc script and even that
(as far back as MCC Interim, AFAICS) doesn't actually fail -
just gives one message during the boot ("Cannot scan for wild
interrupts") and proceeds past that just fine.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-10-13 00:50:52 -04:00
Al Viro 5099d234a5 serial_core: switch to ->[sg]et_serial()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-10-13 00:50:33 -04:00
Greg Kroah-Hartman 817e9bc8cc Revert "serial:serial_core: Allow use of CTS for PPS line discipline"
This reverts commit c550f01c81.

Turns out the samsung tty driver is mucking around in the "unused" port
fields and this patch breaks that code :(

So we need to fix that driver up before this can be accepted.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Steve Sakoman <steve@sakoman.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-04 09:57:45 -07:00
Nicolas Ferre ad8c0eaa0a tty/serial_core: add ISO7816 infrastructure
Add the ISO7816 ioctl and associated accessors and data structure.
Drivers can then use this common implementation to handle ISO7816
(smart cards).

Signed-off-by: Nicolas Ferre <nicolas.ferre@microchip.com>
[ludovic.desroches@microchip.com: squash and rebase, removal of gpios, checkpatch fixes]
Signed-off-by: Ludovic Desroches <ludovic.desroches@microchip.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-02 13:38:55 -07:00
Steve Sakoman c550f01c81 serial:serial_core: Allow use of CTS for PPS line discipline
Add a "pps_4wire" file to serial ports in sysfs in case the kernel is
configured with CONFIG_PPS_CLIENT_LDISC. Writing 1 to the file enables
the use of CTS instead of DCD for PPS signal input. This is necessary
in case a serial port is not completely wired.
Though this affects PPS processing the patch is against the serial core
as the source of the serial port PPS event dispatching has to be
modified. Furthermore it should be possible to modify the source of
serial port PPS event dispatching before changing the line discipline.

Signed-off-by: Andreas Steinmetz <ast@domdv.de>
Signed-off-by: Steve Sakoman <steve@sakoman.com>
Tested-by: Steve Sakoman <steve@sakoman.com>
Tested-by: Eric Gallimore <egallimore@ucsd.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-02 13:38:55 -07:00
Tycho Andersen a5ba1d95e4 uart: fix race between uart_put_char() and uart_shutdown()
We have reports of the following crash:

    PID: 7 TASK: ffff88085c6d61c0 CPU: 1 COMMAND: "kworker/u25:0"
    #0 [ffff88085c6db710] machine_kexec at ffffffff81046239
    #1 [ffff88085c6db760] crash_kexec at ffffffff810fc248
    #2 [ffff88085c6db830] oops_end at ffffffff81008ae7
    #3 [ffff88085c6db860] no_context at ffffffff81050b8f
    #4 [ffff88085c6db8b0] __bad_area_nosemaphore at ffffffff81050d75
    #5 [ffff88085c6db900] bad_area_nosemaphore at ffffffff81050e83
    #6 [ffff88085c6db910] __do_page_fault at ffffffff8105132e
    #7 [ffff88085c6db9b0] do_page_fault at ffffffff8105152c
    #8 [ffff88085c6db9c0] page_fault at ffffffff81a3f122
    [exception RIP: uart_put_char+149]
    RIP: ffffffff814b67b5 RSP: ffff88085c6dba78 RFLAGS: 00010006
    RAX: 0000000000000292 RBX: ffffffff827c5120 RCX: 0000000000000081
    RDX: 0000000000000000 RSI: 000000000000005f RDI: ffffffff827c5120
    RBP: ffff88085c6dba98 R8: 000000000000012c R9: ffffffff822ea320
    R10: ffff88085fe4db04 R11: 0000000000000001 R12: ffff881059f9c000
    R13: 0000000000000001 R14: 000000000000005f R15: 0000000000000fba
    ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018
    #9 [ffff88085c6dbaa0] tty_put_char at ffffffff81497544
    #10 [ffff88085c6dbac0] do_output_char at ffffffff8149c91c
    #11 [ffff88085c6dbae0] __process_echoes at ffffffff8149cb8b
    #12 [ffff88085c6dbb30] commit_echoes at ffffffff8149cdc2
    #13 [ffff88085c6dbb60] n_tty_receive_buf_fast at ffffffff8149e49b
    #14 [ffff88085c6dbbc0] __receive_buf at ffffffff8149ef5a
    #15 [ffff88085c6dbc20] n_tty_receive_buf_common at ffffffff8149f016
    #16 [ffff88085c6dbca0] n_tty_receive_buf2 at ffffffff8149f194
    #17 [ffff88085c6dbcb0] flush_to_ldisc at ffffffff814a238a
    #18 [ffff88085c6dbd50] process_one_work at ffffffff81090be2
    #19 [ffff88085c6dbe20] worker_thread at ffffffff81091b4d
    #20 [ffff88085c6dbeb0] kthread at ffffffff81096384
    #21 [ffff88085c6dbf50] ret_from_fork at ffffffff81a3d69f​

after slogging through some dissasembly:

ffffffff814b6720 <uart_put_char>:
ffffffff814b6720:	55                   	push   %rbp
ffffffff814b6721:	48 89 e5             	mov    %rsp,%rbp
ffffffff814b6724:	48 83 ec 20          	sub    $0x20,%rsp
ffffffff814b6728:	48 89 1c 24          	mov    %rbx,(%rsp)
ffffffff814b672c:	4c 89 64 24 08       	mov    %r12,0x8(%rsp)
ffffffff814b6731:	4c 89 6c 24 10       	mov    %r13,0x10(%rsp)
ffffffff814b6736:	4c 89 74 24 18       	mov    %r14,0x18(%rsp)
ffffffff814b673b:	e8 b0 8e 58 00       	callq  ffffffff81a3f5f0 <mcount>
ffffffff814b6740:	4c 8b a7 88 02 00 00 	mov    0x288(%rdi),%r12
ffffffff814b6747:	45 31 ed             	xor    %r13d,%r13d
ffffffff814b674a:	41 89 f6             	mov    %esi,%r14d
ffffffff814b674d:	49 83 bc 24 70 01 00 	cmpq   $0x0,0x170(%r12)
ffffffff814b6754:	00 00
ffffffff814b6756:	49 8b 9c 24 80 01 00 	mov    0x180(%r12),%rbx
ffffffff814b675d:	00
ffffffff814b675e:	74 2f                	je     ffffffff814b678f <uart_put_char+0x6f>
ffffffff814b6760:	48 89 df             	mov    %rbx,%rdi
ffffffff814b6763:	e8 a8 67 58 00       	callq  ffffffff81a3cf10 <_raw_spin_lock_irqsave>
ffffffff814b6768:	41 8b 8c 24 78 01 00 	mov    0x178(%r12),%ecx
ffffffff814b676f:	00
ffffffff814b6770:	89 ca                	mov    %ecx,%edx
ffffffff814b6772:	f7 d2                	not    %edx
ffffffff814b6774:	41 03 94 24 7c 01 00 	add    0x17c(%r12),%edx
ffffffff814b677b:	00
ffffffff814b677c:	81 e2 ff 0f 00 00    	and    $0xfff,%edx
ffffffff814b6782:	75 23                	jne    ffffffff814b67a7 <uart_put_char+0x87>
ffffffff814b6784:	48 89 c6             	mov    %rax,%rsi
ffffffff814b6787:	48 89 df             	mov    %rbx,%rdi
ffffffff814b678a:	e8 e1 64 58 00       	callq  ffffffff81a3cc70 <_raw_spin_unlock_irqrestore>
ffffffff814b678f:	44 89 e8             	mov    %r13d,%eax
ffffffff814b6792:	48 8b 1c 24          	mov    (%rsp),%rbx
ffffffff814b6796:	4c 8b 64 24 08       	mov    0x8(%rsp),%r12
ffffffff814b679b:	4c 8b 6c 24 10       	mov    0x10(%rsp),%r13
ffffffff814b67a0:	4c 8b 74 24 18       	mov    0x18(%rsp),%r14
ffffffff814b67a5:	c9                   	leaveq
ffffffff814b67a6:	c3                   	retq
ffffffff814b67a7:	49 8b 94 24 70 01 00 	mov    0x170(%r12),%rdx
ffffffff814b67ae:	00
ffffffff814b67af:	48 63 c9             	movslq %ecx,%rcx
ffffffff814b67b2:	41 b5 01             	mov    $0x1,%r13b
ffffffff814b67b5:	44 88 34 0a          	mov    %r14b,(%rdx,%rcx,1)
ffffffff814b67b9:	41 8b 94 24 78 01 00 	mov    0x178(%r12),%edx
ffffffff814b67c0:	00
ffffffff814b67c1:	83 c2 01             	add    $0x1,%edx
ffffffff814b67c4:	81 e2 ff 0f 00 00    	and    $0xfff,%edx
ffffffff814b67ca:	41 89 94 24 78 01 00 	mov    %edx,0x178(%r12)
ffffffff814b67d1:	00
ffffffff814b67d2:	eb b0                	jmp    ffffffff814b6784 <uart_put_char+0x64>
ffffffff814b67d4:	66 66 66 2e 0f 1f 84 	data32 data32 nopw %cs:0x0(%rax,%rax,1)
ffffffff814b67db:	00 00 00 00 00

for our build, this is crashing at:

    circ->buf[circ->head] = c;

Looking in uart_port_startup(), it seems that circ->buf (state->xmit.buf)
protected by the "per-port mutex", which based on uart_port_check() is
state->port.mutex. Indeed, the lock acquired in uart_put_char() is
uport->lock, i.e. not the same lock.

Anyway, since the lock is not acquired, if uart_shutdown() is called, the
last chunk of that function may release state->xmit.buf before its assigned
to null, and cause the race above.

To fix it, let's lock uport->lock when allocating/deallocating
state->xmit.buf in addition to the per-port mutex.

v2: switch to locking uport->lock on allocation/deallocation instead of
    locking the per-port mutex in uart_put_char. Note that since
    uport->lock is a spin lock, we have to switch the allocation to
    GFP_ATOMIC.
v3: move the allocation outside the lock, so we can switch back to
    GFP_KERNEL

Signed-off-by: Tycho Andersen <tycho@tycho.ws>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-13 11:26:43 +02:00
Kees Cook 6396bb2215 treewide: kzalloc() -> kcalloc()
The kzalloc() function has a 2-factor argument form, kcalloc(). This
patch replaces cases of:

        kzalloc(a * b, gfp)

with:
        kcalloc(a * b, gfp)

as well as handling cases of:

        kzalloc(a * b * c, gfp)

with:

        kzalloc(array3_size(a, b, c), gfp)

as it's slightly less ugly than:

        kzalloc_array(array_size(a, b), c, gfp)

This does, however, attempt to ignore constant size factors like:

        kzalloc(4 * 1024, gfp)

though any constants defined via macros get caught up in the conversion.

Any factors with a sizeof() of "unsigned char", "char", and "u8" were
dropped, since they're redundant.

The Coccinelle script used for this was:

// Fix redundant parens around sizeof().
@@
type TYPE;
expression THING, E;
@@

(
  kzalloc(
-	(sizeof(TYPE)) * E
+	sizeof(TYPE) * E
  , ...)
|
  kzalloc(
-	(sizeof(THING)) * E
+	sizeof(THING) * E
  , ...)
)

// Drop single-byte sizes and redundant parens.
@@
expression COUNT;
typedef u8;
typedef __u8;
@@

(
  kzalloc(
-	sizeof(u8) * (COUNT)
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(__u8) * (COUNT)
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(char) * (COUNT)
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(unsigned char) * (COUNT)
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(u8) * COUNT
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(__u8) * COUNT
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(char) * COUNT
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(unsigned char) * COUNT
+	COUNT
  , ...)
)

// 2-factor product with sizeof(type/expression) and identifier or constant.
@@
type TYPE;
expression THING;
identifier COUNT_ID;
constant COUNT_CONST;
@@

(
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * (COUNT_ID)
+	COUNT_ID, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * COUNT_ID
+	COUNT_ID, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * (COUNT_CONST)
+	COUNT_CONST, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * COUNT_CONST
+	COUNT_CONST, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * (COUNT_ID)
+	COUNT_ID, sizeof(THING)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * COUNT_ID
+	COUNT_ID, sizeof(THING)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * (COUNT_CONST)
+	COUNT_CONST, sizeof(THING)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * COUNT_CONST
+	COUNT_CONST, sizeof(THING)
  , ...)
)

// 2-factor product, only identifiers.
@@
identifier SIZE, COUNT;
@@

- kzalloc
+ kcalloc
  (
-	SIZE * COUNT
+	COUNT, SIZE
  , ...)

// 3-factor product with 1 sizeof(type) or sizeof(expression), with
// redundant parens removed.
@@
expression THING;
identifier STRIDE, COUNT;
type TYPE;
@@

(
  kzalloc(
-	sizeof(TYPE) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kzalloc(
-	sizeof(TYPE) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kzalloc(
-	sizeof(TYPE) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kzalloc(
-	sizeof(TYPE) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kzalloc(
-	sizeof(THING) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kzalloc(
-	sizeof(THING) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kzalloc(
-	sizeof(THING) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kzalloc(
-	sizeof(THING) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
)

// 3-factor product with 2 sizeof(variable), with redundant parens removed.
@@
expression THING1, THING2;
identifier COUNT;
type TYPE1, TYPE2;
@@

(
  kzalloc(
-	sizeof(TYPE1) * sizeof(TYPE2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  kzalloc(
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  kzalloc(
-	sizeof(THING1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  kzalloc(
-	sizeof(THING1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  kzalloc(
-	sizeof(TYPE1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
|
  kzalloc(
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
)

// 3-factor product, only identifiers, with redundant parens removed.
@@
identifier STRIDE, SIZE, COUNT;
@@

(
  kzalloc(
-	(COUNT) * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	COUNT * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	COUNT * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	(COUNT) * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	COUNT * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	(COUNT) * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	(COUNT) * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	COUNT * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
)

// Any remaining multi-factor products, first at least 3-factor products,
// when they're not all constants...
@@
expression E1, E2, E3;
constant C1, C2, C3;
@@

(
  kzalloc(C1 * C2 * C3, ...)
|
  kzalloc(
-	(E1) * E2 * E3
+	array3_size(E1, E2, E3)
  , ...)
|
  kzalloc(
-	(E1) * (E2) * E3
+	array3_size(E1, E2, E3)
  , ...)
|
  kzalloc(
-	(E1) * (E2) * (E3)
+	array3_size(E1, E2, E3)
  , ...)
|
  kzalloc(
-	E1 * E2 * E3
+	array3_size(E1, E2, E3)
  , ...)
)

// And then all remaining 2 factors products when they're not all constants,
// keeping sizeof() as the second factor argument.
@@
expression THING, E1, E2;
type TYPE;
constant C1, C2, C3;
@@

(
  kzalloc(sizeof(THING) * C2, ...)
|
  kzalloc(sizeof(TYPE) * C2, ...)
|
  kzalloc(C1 * C2 * C3, ...)
|
  kzalloc(C1 * C2, ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * (E2)
+	E2, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * E2
+	E2, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * (E2)
+	E2, sizeof(THING)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * E2
+	E2, sizeof(THING)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	(E1) * E2
+	E1, E2
  , ...)
|
- kzalloc
+ kcalloc
  (
-	(E1) * (E2)
+	E1, E2
  , ...)
|
- kzalloc
+ kcalloc
  (
-	E1 * E2
+	E1, E2
  , ...)
)

Signed-off-by: Kees Cook <keescook@chromium.org>
2018-06-12 16:19:22 -07:00
Linus Torvalds a22e48cf31 TTY/Serial patches for 4.18-rc1
Here is the big tty/serial driver update for 4.18-rc1.
 
 There's nothing major here, just lots of serial driver updates.  Full
 details are in the shortlog, nothing anything specific to call out here.
 
 All have been in linux-next for a while with no reported issues.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
 -----BEGIN PGP SIGNATURE-----
 
 iG0EABECAC0WIQT0tgzFv3jCIUoxPcsxR9QN2y37KQUCWxbZzQ8cZ3JlZ0Brcm9h
 aC5jb20ACgkQMUfUDdst+ym2pQCggrWJsOeXLXgzhVDH6/qMFP9R/hEAoLTvmOWQ
 BlPIlvRDm/ud33VogJ8t
 =XS8u
 -----END PGP SIGNATURE-----

Merge tag 'tty-4.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty/serial updates from Greg KH:
 "Here is the big tty/serial driver update for 4.18-rc1.

  There's nothing major here, just lots of serial driver updates. Full
  details are in the shortlog, nothing anything specific to call out
  here.

  All have been in linux-next for a while with no reported issues"

* tag 'tty-4.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (55 commits)
  vt: Perform safe console erase only once
  serial: imx: disable UCR4_OREN on shutdown
  serial: imx: drop CTS/RTS handling from shutdown
  tty: fix typo in ASYNCB_FOURPORT comment
  serial: samsung: check DMA engine capabilities before using DMA mode
  tty: Fix data race in tty_insert_flip_string_fixed_flag
  tty: serial: msm_geni_serial: Fix TX infinite loop
  serial: 8250_dw: Fix runtime PM handling
  serial: 8250: omap: Fix idling of clocks for unused uarts
  tty: serial: drop ATH79 specific SoC symbols
  serial: 8250: Add missing rxtrig_bytes on Altera 16550 UART
  serial/aspeed-vuart: fix a couple mod_timer() calls
  serial: sh-sci: Use spin_{try}lock_irqsave instead of open coding version
  serial: 8250_of: Add IO space support
  tty/serial: atmel: use port->name as name in request_irq()
  serial: imx: dma_unmap_sg buffers on shutdown
  serial: imx: cleanup imx_uart_disable_dma()
  tty: serial: qcom_geni_serial: Add early console support
  tty: serial: qcom_geni_serial: Return IRQ_NONE for spurious interrupts
  tty: serial: qcom_geni_serial: Use iowrite32_rep to write to FIFO
  ...
2018-06-05 16:55:56 -07:00
Christoph Hellwig 8a8dcabffb tty: replace ->proc_fops with ->proc_show
Just set up the show callback in the tty_operations, and use
proc_create_single_data to create the file without additional
boilerplace code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-05-16 07:24:30 +02:00
Jeremy Kerr c5f78b1fe4 serial: Introduce UPSTAT_SYNC_FIFO for synchronised FIFOs
This change adds a flag to indicate that a UART is has an external means
of synchronising its FIFO, without needing CTSRTS or XON/XOFF.

This allows us to use the throttle/unthrottle callbacks, without having
to claim other methods of flow control.

Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Tested-by: Eddie James <eajames@linux.vnet.ibm.com>
Tested-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-23 10:16:50 +02:00
Jeremy Kerr 4f79409779 serial: expose buf_overrun count through proc interface
The buf_overrun count is only every written, and not exposed to
userspace anywhere. This means that dropped characters due to flip
buffer overruns are never visible to userspace.

The /proc/tty/driver/serial file exports a bunch of metrics (including
hardware overruns) already, so add the buf_overrun (as "bo:") to this
file.

Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-23 16:34:06 +01:00
Sebastian Andrzej Siewior 714569064a serial: core: mark port as initialized in autoconfig
This is a followup on 44117a1d17 ("serial: core: mark port as
initialized after successful IRQ change").
Nikola has been using autoconfig via setserial and reported a crash
similar to what I fixed in the earlier mentioned commit. Here I do the
same fixup for the autoconfig. I wasn't sure that this is the right
approach. Nikola confirmed that it fixes his crash.

Fixes: b3b5764618 ("tty: serial_core: convert uart_open to use tty_port_open")
Link: http://lkml.kernel.org/r/20180131072000.GD1853@localhost.localdomain
Reported-by: Nikola Ciprich <nikola.ciprich@linuxbox.cz>
Tested-by: Nikola Ciprich <nikola.ciprich@linuxbox.cz>
Cc: <stable@vger.kernel.org>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Tested-by: Nikola Ciprich <nikola.ciprich@linuxbox.cz>
Acked-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28 13:48:21 +01:00
Sebastian Andrzej Siewior 44117a1d17 serial: core: mark port as initialized after successful IRQ change
setserial changes the IRQ via uart_set_info(). It invokes
uart_shutdown() which free the current used IRQ and clear
TTY_PORT_INITIALIZED. It will then update the IRQ number and invoke
uart_startup() before returning to the caller leaving
TTY_PORT_INITIALIZED cleared.

The next open will crash with
|  list_add double add: new=ffffffff839fcc98, prev=ffffffff839fcc98, next=ffffffff839fcc98.
since the close from the IOCTL won't free the IRQ (and clean the list)
due to the TTY_PORT_INITIALIZED check in uart_shutdown().

There is same pattern in uart_do_autoconfig() and I *think* it also
needs to set TTY_PORT_INITIALIZED there.
Is there a reason why uart_startup() does not set the flag by itself
after the IRQ has been acquired (since it is cleared in uart_shutdown)?

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-22 14:20:56 +01:00
Paul Cercueil 0f646b63a1 serial: core: Make uart_parse_options take const char* argument
The pointed string is never modified from within uart_parse_options, so
it should be marked as const in the function prototype.

Signed-off-by: Paul Cercueil <paul@crapouillou.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-09 16:46:26 +01:00
Lukas Wunner f1e5b618c1 serial: core: Support common rs485 binding for RTS polarity
When a driver invokes the uart_get_rs485_mode() helper, set the RTS
polarity to active high by default unless the newly introduced
"rs485-rts-active-low" property was specified.

imx contains a line to set the default RTS polarity to active high,
it is now superfluous and hence deleted.

omap-serial historically defaults to active low and supports an
"rs485-rts-active-high" property to inverse the polarity.
Retain that behavior for compatibility.

Cc: Mark Jackson <mpfj@newflow.co.uk>
Cc: Michał Oleszczyk <oleszczyk.m@gmail.com>
Cc: Rafael Gago Castano <rgc@hms.se>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-28 16:05:19 +01:00
Lukas Wunner 743f93f822 serial: Make retrieval of rs485 properties platform-agnostic
Commit ef838a81dd ("serial: Add common rs485 device tree parsing
function") consolidated retrieval of rs485 OF properties in a common
helper function but did not #ifdef it to CONFIG_OF.  The function is
therefore included on ACPI platforms as well even though it's not used.

On the other hand ACPI platforms with rs485 do exist (e.g. Siemens
IOT2040) and they may leverage _DSD to store rs485 properties.  Likewise,
UART platform devices instantiated from an MFD should be able to specify
rs485 properties.  In fact, the tty subsystem maintainer had asked for
a "generic" function during review of commit ef838a81dd4d:
https://marc.info/?l=linux-serial&m=150143441725194&w=4

Thus, instead of constraining the helper to OF platforms, make it
platform-agnostic by converting it to device_property_*() functions
and renaming it accordingly.

In imx.c, move the invocation of uart_get_rs485_mode() from
serial_imx_probe_dt() to serial_imx_probe() so that it also gets called
for non-OF devices.

In omap-serial.c, move its invocation further up within
serial_omap_probe_rs485() so that the RTS polarity can be overridden
with the driver-specific "rs485-rts-active-high" property once we
introduce a generic "rs485-rts-active-low" property.

Cc: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Richard Genoud <richard.genoud@gmail.com>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-28 16:04:57 +01:00
Greg Kroah-Hartman 4793f2ebff tty: serial: Remove redundant license text
Now that the SPDX tag is in all tty files, that identifies the license
in a specific and legally-defined manner.  So the extra GPL text wording
can be removed as it is no longer needed at all.

This is done on a quest to remove the 700+ different ways that files in
the kernel describe the GPL license text.  And there's unneeded stuff
like the address (sometimes incorrect) for the FSF which is never
needed.

No copyright headers or other non-license-description text was removed.

Cc: Jiri Slaby <jslaby@suse.com>
Cc: Eric Anholt <eric@anholt.net>
Cc: Stefan Wahren <stefan.wahren@i2se.com>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: Ray Jui <rjui@broadcom.com>
Cc: Scott Branden <sbranden@broadcom.com>
Cc: bcm-kernel-feedback-list@broadcom.com
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Helge Deller <deller@gmx.de>
Cc: Joachim Eastwood <manabian@gmail.com>
Cc: Matthias Brugger <matthias.bgg@gmail.com>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Tobias Klauser <tklauser@distanz.ch>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Richard Genoud <richard.genoud@gmail.com>
Cc: Alexander Shiyan <shc_work@mail.ru>
Cc: Baruch Siach <baruch@tkos.co.il>
Cc: Pat Gefre <pfg@sgi.com>
Cc: "Guilherme G. Piccoli" <gpiccoli@linux.vnet.ibm.com>
Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: Vladimir Zapolskiy <vz@mleia.com>
Cc: Sylvain Lemieux <slemieux.tyco@gmail.com>
Cc: Carlo Caione <carlo@caione.org>
Cc: Kevin Hilman <khilman@baylibre.com>
Cc: Liviu Dudau <liviu.dudau@arm.com>
Cc: Sudeep Holla <sudeep.holla@arm.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Andy Gross <andy.gross@linaro.org>
Cc: David Brown <david.brown@linaro.org>
Cc: "Andreas Färber" <afaerber@suse.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Kevin Cernekee <cernekee@gmail.com>
Cc: Laxman Dewangan <ldewangan@nvidia.com>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Jonathan Hunter <jonathanh@nvidia.com>
Cc: Barry Song <baohua@kernel.org>
Cc: Patrice Chotard <patrice.chotard@st.com>
Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Cc: Alexandre Torgue <alexandre.torgue@st.com>
Cc: Chris Metcalf <cmetcalf@mellanox.com>
Cc: Peter Korsgaard <jacmet@sunsite.dk>
Cc: Timur Tabi <timur@tabi.org>
Cc: Tony Prisk <linux@prisktech.co.nz>
Cc: Michal Simek <michal.simek@xilinx.com>
Cc: "Sören Brinkmann" <soren.brinkmann@xilinx.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-08 13:08:12 +01:00
Greg Kroah-Hartman e3b3d0f549 tty: add SPDX identifiers to all remaining files in drivers/tty/
It's good to have SPDX identifiers in all files to make it easier to
audit the kernel tree for correct licenses.

Update the drivers/tty files files with the correct SPDX license
identifier based on the license text in the file itself.  The SPDX
identifier is a legally binding shorthand, which can be used instead of
the full boiler plate text.

This work is based on a script and data from Thomas Gleixner, Philippe
Ombredanne, and Kate Stewart.

Cc: Jiri Slaby <jslaby@suse.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Chris Metcalf <cmetcalf@mellanox.com>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: David Sterba <dsterba@suse.com>
Cc: James Hogan <jhogan@kernel.org>
Cc: Rob Herring <robh@kernel.org>
Cc: Eric Anholt <eric@anholt.net>
Cc: Stefan Wahren <stefan.wahren@i2se.com>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: Ray Jui <rjui@broadcom.com>
Cc: Scott Branden <sbranden@broadcom.com>
Cc: bcm-kernel-feedback-list@broadcom.com
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Helge Deller <deller@gmx.de>
Cc: Joachim Eastwood <manabian@gmail.com>
Cc: Matthias Brugger <matthias.bgg@gmail.com>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Tobias Klauser <tklauser@distanz.ch>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Richard Genoud <richard.genoud@gmail.com>
Cc: Alexander Shiyan <shc_work@mail.ru>
Cc: Baruch Siach <baruch@tkos.co.il>
Cc: "Maciej W. Rozycki" <macro@linux-mips.org>
Cc: "Uwe Kleine-König" <kernel@pengutronix.de>
Cc: Pat Gefre <pfg@sgi.com>
Cc: "Guilherme G. Piccoli" <gpiccoli@linux.vnet.ibm.com>
Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: Vladimir Zapolskiy <vz@mleia.com>
Cc: Sylvain Lemieux <slemieux.tyco@gmail.com>
Cc: Carlo Caione <carlo@caione.org>
Cc: Kevin Hilman <khilman@baylibre.com>
Cc: Liviu Dudau <liviu.dudau@arm.com>
Cc: Sudeep Holla <sudeep.holla@arm.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Andy Gross <andy.gross@linaro.org>
Cc: David Brown <david.brown@linaro.org>
Cc: "Andreas Färber" <afaerber@suse.de>
Cc: Kevin Cernekee <cernekee@gmail.com>
Cc: Laxman Dewangan <ldewangan@nvidia.com>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Jonathan Hunter <jonathanh@nvidia.com>
Cc: Barry Song <baohua@kernel.org>
Cc: Patrice Chotard <patrice.chotard@st.com>
Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Cc: Alexandre Torgue <alexandre.torgue@st.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Peter Korsgaard <jacmet@sunsite.dk>
Cc: Timur Tabi <timur@tabi.org>
Cc: Tony Prisk <linux@prisktech.co.nz>
Cc: Michal Simek <michal.simek@xilinx.com>
Cc: "Sören Brinkmann" <soren.brinkmann@xilinx.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Cc: Philippe Ombredanne <pombredanne@nexb.com>
Cc: Jiri Slaby <jslaby@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-08 13:08:12 +01:00
Colin Ian King 9356335faf serial: core: remove redundant assignment to port
The final assignment to port is never read, hence it is redundant
and can be removed. Also move the declaration of port to a more
local scope.  Cleans up clang warning:

drivers/tty/serial/serial_core.c:1498:2: warning: Value stored
to 'port' is never read

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-04 12:08:53 +01:00
Uwe Kleine-König ef838a81dd serial: Add common rs485 device tree parsing function
Several drivers have the same device tree parsing code. Create
a common helper function for it.

This patch bases on work done by Sascha Hauer.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-09-18 18:36:25 +02:00
Rafael Gago a6845e1e1b serial: core: Consider rs485 settings to drive RTS
Previously the rs485 settings weren't considered when setting the RTS
line, so e.g. closing and reopening a port made serial_core to drive
the line as if rs485 was disabled.

This patch fixes those issues.

Signed-off-by: Rafael Gago Castano <rgc@hms.se>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-08-28 20:51:20 +02:00
Andy Shevchenko aef3ad103a serial: core: remove unneeded irq_wake flag
There is no need to duplicate a flag which IRQ core takes care of.

Replace custom flag by IRQ core API that retrieves its state.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-08-28 20:51:20 +02:00
Andy Shevchenko a17e74c533 serial: core: enforce type for upf_t when copying
upf_t is a bitwise defined type and any assignment from different, but
compatible, types makes static analyzer unhappy.

drivers/tty/serial/serial_core.c:793:29: warning: incorrect type in assignment (different base types)
drivers/tty/serial/serial_core.c:793:29:    expected int [signed] flags
drivers/tty/serial/serial_core.c:793:29:    got restricted upf_t [usertype] flags
drivers/tty/serial/serial_core.c:867:19: warning: incorrect type in assignment (different base types)
drivers/tty/serial/serial_core.c:867:19:    expected restricted upf_t [usertype] new_flags
drivers/tty/serial/serial_core.c:867:19:    got int [signed] flags

Enforce corresponding types when upf_t being assigned.

Note, we need __force attribute due to the scope of variable. It's being
used in user space with plain old type while kernel uses bitwise one.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-30 07:44:22 -07:00
Johan Hovold dc2f727159 serial: rate limit custom-speed deprecation notice
Contrary to what a comment claimed, the ASYNC_SPD flags and custom
divisor can be set by a non-privileged user so rate limit the
deprecation notice as was intended.

Signed-off-by: Johan Hovold <johan@kernel.org>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-13 11:49:57 +02:00
Johan Hovold da4c279942 serial: enable serdev support
Enable serdev support by using the new device-registration helpers.

Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18 17:38:25 +02:00
Lucas Stach 88e2582e90 serial: core: fix crash in uart_suspend_port
With serdev we might end up with serial ports that have no cdev exported
to userspace, as they are used as the bus interface to other devices. In
that case serial_match_port() won't be able to find a matching tty_dev.

Skip the irq wakeup enabling in that case, as serdev will make sure to
keep the port active, as long as there are devices depending on it.

Fixes: 8ee3fde047 (tty_port: register tty ports with serdev bus)
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18 16:43:55 +02:00
Andy Shevchenko cade3580f7 serial: core: Re-use struct uart_port {name} field
Since we have port name stored in struct uart_port, we better to use
that one instead of open coding.

This will make it one place source for easier maintenance or
modifications.

While here, replace printk(KERN_INFO ) by pr_info(). It seems last printk()
call in serial_core.c.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-04-08 18:51:57 +02:00
Vignesh R f7048b1590 tty: serial_core: Add name field to uart_port struct
Introduce a field to store name of uart_port that can be used to easily
identify UART port instances on a system that has more than one UART
instance. The name is of the form ttyXN(eg. ttyS0, ttyAMA0,..) where N
is number that particular UART instance.
This field will be useful when printing debug info for a particular port
or in register IRQs with unique IRQ name. Port name is populated during
uart_add_one_port().

Signed-off-by: Vignesh R <vigneshr@ti.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-03-31 16:56:10 +02:00
Jiri Slaby 22077b091a tty: serial_core, remove state checks in uart_poll*
Coverity complains about uart_state checks in polling functions. And it
is indeed correct. We do something like this:
	struct uart_state *state = drv->state + line;
	if (!state)
		return;

Adding 'line' to drv->state would move the potential NULL pointer to
something near NULL and the check is useless. Even if we checked pure
drv->state, nothing guarantees it is not freed and NULLed after the
check. So if the only user of this interface (kgdboc) needs to assure
something, this is neither the correct thing, nor place to do so.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: linux-serial@vger.kernel.org
Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: kgdb-bugreport@lists.sourceforge.net
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-03-17 14:17:11 +09:00
Ingo Molnar 174cd4b1e5 sched/headers: Prepare to move signal wakeup & sigpending methods from <linux/sched.h> into <linux/sched/signal.h>
Fix up affected files that include this signal functionality via sched.h.

Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-02 08:42:32 +01:00
Linus Torvalds 7c0f6ba682 Replace <asm/uaccess.h> with <linux/uaccess.h> globally
This was entirely automated, using the script by Al:

  PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>'
  sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \
        $(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h)

to do the replacement at the end of the merge window.

Requested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-24 11:46:01 -08:00
Andy Shevchenko ef510bea5f serial: core: don't check port twice in a row
There is no need to check port for NULL in uart_port_deref() since we call it
only when port is defined.

There are few places that violate this. Fix them here as well.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-28 08:29:34 +01:00
Rob Herring d0f4bce2bc tty: serial_core: fix NULL struct tty pointer access in uart_write_wakeup
Since commit 761ed4a945 ("tty: serial_core: convert uart_close to
use tty_port_close"), the serial console is broken on various systems
and typing "reboot" splats the following on the serial console:

INIT: Sending p[  427.863916] BUG: unable to handle kernel NULL pointer dereference at 00000000000001e0
[  427.885156] IP: [] tty_wakeup+0xc/0x70
[  427.898337] PGD 0 [  427.902051]
[  427.907498] Oops: 0000 [#1] PREEMPT SMP
[  427.917635] Modules linked in: nfsv3 nfs_acl nfs fscache lockd
sunrpc grace edd af_packet cpufreq_conservative cpufreq_userspace
cpufreq_powersave fuse loop md_mod dm_mod joydev hid_generic usbhid
ipmi_ssif ohci_pci ohci_hcd ehci_pci ehci_hcd e1000e ptp firewire_ohci
edac_core pps_core tpm_infineon sp5100_tco firewire_core acpi_cpufreq
serio_raw pcspkr fjes usbcore shpchp edac_mce_amd tpm_tis ipmi_si
tpm_tis_core i2c_piix4 k10temp sg ipmi_msghandler tpm sr_mod button
cdrom kvm_amd kvm irqbypass crc_itu_t ast ttm drm_kms_helper drm
fb_sys_fops sysimgblt sysfillrect syscopyarea i2c_algo_bit scsi_dh_rdac
scsi_dh_alua scsi_dh_emc scsi_dh_hp_sw ata_generic pata_atiixp
[  428.054179] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.9.0-rc1-1.g73e3f23-default #1
[  428.072868] Hardware name: System manufacturer System Product Name/KGP(M)E-D16, BIOS 0902    12/03/2010
[  428.094755] task: ffffffffa2c0d500 task.stack: ffffffffa2c00000
[  428.109717] RIP: 0010:[]  [] tty_wakeup+0xc/0x70
[  428.128407] RSP: 0018:ffff9a1a5fc03df8  EFLAGS: 00010086
[  428.142184] RAX: ffff9a1857258000 RBX: ffffffffa3050ea0 RCX: 0000000000000000
[  428.159649] RDX: 000000000000001b RSI: 0000000000000000 RDI: 0000000000000000
[  428.177109] RBP: ffff9a1a5fc03e08 R08: 0000000000000000 R09: 0000000000000000
[  428.194547] R10: 0000000000021c77 R11: 0000000000000000 R12: ffff9a1857258000
[  428.212002] R13: 0000000000000000 R14: 0000000000000020 R15: 0000000000000020
[  428.229481] FS:  0000000000000000(0000) GS:ffff9a1a5fc00000(0000) knlGS:0000000000000000
[  428.248938] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  428.263726] CR2: 00000000000001e0 CR3: 0000000390c06000 CR4: 00000000000006f0
[  428.281331] Stack:
[  428.288696]  ffffffffa3050ea0 ffff9a1857258000 ffff9a1a5fc03e18 ffffffffa24e0ab1
[  428.307064]  ffff9a1a5fc03e40 ffffffffa24e8865 ffffffffa3050ea0 00000000000000c2
[  428.325456]  0000000000000046 ffff9a1a5fc03e78 ffffffffa24e8a5f ffffffffa3050ea0
[  428.343905] Call Trace:
[  428.352319]   [  428.356216]  [] uart_write_wakeup+0x21/0x30

The problem is for console ports, the serial port is not shutdown and
interrupts may fire after the struct tty is gone. Simply calling the
tty_port helper tty_port_tty_wakeup instead of tty_wakeup directly will
ensure there is a valid struct tty.

Fixes: 761ed4a945 ("tty: serial_core: convert uart_close to use tty_port_close")
Reported-by: Borislav Petkov <bp@alien8.de>
Reported-by: Mike Galbraith <mgalbraith@suse.de>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: linux-serial@vger.kernel.org
Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-10-28 08:13:07 -04:00
Geert Uytterhoeven 4dda864d73 tty: serial_core: Fix serial console crash on port shutdown
The port->console flag is always false, as uart_console() is called
before the serial console has been registered.

Hence for a serial port used as the console, uart_tty_port_shutdown()
will still be called when userspace closes the port, powering it down.
This may lead to a system lock up when the serial console driver writes
to the serial port's registers.

To fix this, move the setting of port->console after the call to
uart_configure_port(), which registers the serial console.

Fixes: 761ed4a945 ("tty: serial_core: convert uart_close to use tty_port_close")
Reported-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Rob Herring <robh@kernel.org>
Tested-by: Mugunthan V N <mugunthanvnm@ti.com>
Tested-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
[robh: rebased on tty-linus]
Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-10-28 08:13:07 -04:00
Rob Herring be2c92b8f1 serial: core: fix console problems on uart_close
Commit 761ed4a945 ('tty: serial_core: convert uart_close to use
tty_port_close') started setting the ttyport console flag for serial
drivers. This is causing crashes, hangs, or garbage output on several
platforms because the serial shutdown is skipped and IRQs are left
enabled.

Partially revert commit 761ed4a945 and drop reporting UART tty_ports
as a console leaving the console handling to the serial_core as it was
before.

Fixes: 761ed4a945 ("tty: serial_core: convert uart_close to use tty_port_close")
Reported-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Reported-by: Mike Galbraith <umgwanakikbuti@gmail.com>
Reported-by: Mugunthan V N <mugunthanvnm@ti.com>
Cc: Peter Hurley <peter@hurleysoftware.com>
Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Alan Cox <alan@linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: linux-serial@vger.kernel.org
Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-10-27 16:02:13 +02:00
Andy Shevchenko a5a2b13074 serial: core: fix potential NULL pointer dereference
The commit 761ed4a945 ("tty: serial_core: convert uart_close to use
tty_port_close") refactored uart_close() to use tty_port_close().  At the same
time it introduced a potential NULL pointer dereference. Rearrange the code to
avoid kernel crash.

Fixes: 761ed4a945 ("tty: serial_core: convert uart_close to use tty_port_close")
Cc: Rob Herring <robh@kernel.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-15 12:35:49 +02:00
Alexander Sverdlin 8b2303de39 serial: core: Fix handling of options after MMIO address
Guenter Roeck reported a regression caused by commit "serial: earlycon:
Extend earlycon command line option to support 64-bit addresses":

console= and earlycon= options have the following format:
...,<addr>,<options>

Historically used here simple_strtoul() had no problems with comma, but the
new and recommended kstrtoull() requires null-terminated string and returns
-EINVAL in case there are "options" at the end. There is no recommended to
use function currently that will support it, so stick to obsolete
simple_strtoull() variant.

Signed-off-by: Alexander Sverdlin <alexander.sverdlin@nokia.com>
Reported-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-13 18:54:34 +02:00
Alexander Sverdlin 46e36683f4 serial: earlycon: Extend earlycon command line option to support 64-bit addresses
earlycon implementation used "unsigned long" internally, but there are systems
(ARM with LPAE) where sizeof(unsigned long) == 4 and uart is mapped beyond 4GiB
address range.

Switch to resource_size_t internally and replace obsoleted simple_strtoul() with
kstrtoull().

Signed-off-by: Alexander Sverdlin <alexander.sverdlin@nokia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-02 15:03:35 +02:00
Rob Herring 761ed4a945 tty: serial_core: convert uart_close to use tty_port_close
tty_port_close handles much of the common parts of tty close. Convert
uart_close to use it and move the serial_core specific parts into
tty_port.shutdown function. This will be needed to use tty_port functions
directly from in kernel clients.

This change causes ops->stop_rx() to be called after uart_wait_until_sent()
is called which I think should be fine. Otherwise, the sequence of the
close should be the same.

Cc: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Rob Herring <robh@kernel.org>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-08-31 15:42:28 +02:00
Rob Herring b3b5764618 tty: serial_core: convert uart_open to use tty_port_open
tty_port_open handles much of the common parts of tty opening. Convert
uart_open to use it and move the serial_core specific parts into
tty_port.activate function. This will be needed to use tty_port functions
directly from in kernel clients.

The tricky part is uart_port_startup can return positive values to allow
setserial to configure the port. We now return the positive value to
tty_port_open so that the tty is not marked as initialized and then set the
return value in uart_open to 0.

Cc: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Rob Herring <robh@kernel.org>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-08-31 15:42:28 +02:00
Fabio Estevam a7cfaf165e serial: serial_core: Perform NULL checks for release/request_port ops
Doing the following UART bind/unbind sequence on a i.mx platform causes
a kernel crash due to NULL pointer dereference:

echo  21f4000.serial > /sys/bus/platform/drivers/imx-uart/bind
echo  21f4000.serial > /sys/bus/platform/drivers/imx-uart/unbind

Fix this problem by adding NULL checks prior to calling release/request_port
ops.

Reported-by: Fugang Duan <fugang.duan@nxp.com>
Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
Tested-by: Fugang Duan <fugang.duan@nxp.com>
Acked-by: Fugang Duan <fugang.duan@nxp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-25 10:40:33 -07:00
Peter Hurley 7da4b8b737 serial: core: Fix port mutex assert if lockdep disabled
commit 4047b37122 ("serial: core: Prevent unsafe uart port access,
part 1") added lockdep assertion for port mutex but fails to check
if debug_locks has disabled lockdep (so lock state is no longer
reliable).

Use lockdep_assert_held() instead, which properly checks lockdep
state as well.

Reported-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Tested-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-05-03 17:53:20 -07:00
Peter Hurley af224ca2df serial: core: Prevent unsafe uart port access, part 3
For tty operations which may expect uart port to have been removed
but still have other necessary work to accomplish, check for NULL
uart port; specifically uart_close(), uart_hangup() and sub-functions
(uart_shutdown() and uart_port_shutdown()).

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-30 09:26:55 -07:00
Peter Hurley 9ed19428a5 serial: core: Prevent unsafe uart port access, part 2
For serial core operations not already excluded by holding port->mutex,
use reference counting to protect deferencing the state->uart_port.

Introduce helper functions, uart_port_ref() and uart_port_deref(), to
wrap uart_port access, and helper macros, uart_port_lock() and
uart_port_unlock(), to wrap combination uart_port access with uart
port lock sections.

Port removal in uart_remove_one_port() waits for reference count to
drop to zero before detaching the uart port from struct uart_state.

For functions only reading the tx circular buffer indexes (where the
uart port lock is claimed to prevent concurrent users), a NULL uart
port is simply ignored and the operation completes normally.

For functions change the tx circular buffer indexes (where the uart
port lock is claimed to prevent concurrent users), the operation is
aborted if the uart port is NULL (ie., has been detached).

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-30 09:26:55 -07:00
Peter Hurley 4047b37122 serial: core: Prevent unsafe uart port access, part 1
uart_remove_one_port() may race with every serial core operation
requiring a valid dereference of state->uart_port. In particular,
uart_remove_one_port() may unlink the uart port concurrently with
any serial core operation that may dereference same.

Ensure safe dereference for those operations that already claim
the port->mutex, and extend that guarantee for trivial cases,
such as the ioctl handlers. Introduce the uart_port_check() helper
which asserts port->mutex is held (only when lockdep is on).

For ioctls, return -EIO as if the port has been hung up (since it has).

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-30 09:26:55 -07:00
Peter Hurley 49c02304fe serial: core: Expand port mutex section in uart_poll_init()
Prepare uart_poll_init() to safely dereference uart port; expand the
port mutex section to guarantee uart port remains valid until
uart_poll_init() completes.

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-30 09:26:55 -07:00
Peter Hurley d41861ca19 tty: Replace ASYNC_INITIALIZED bit and update atomically
Replace ASYNC_INITIALIZED bit in the tty_port::flags field with
TTY_PORT_INITIALIZED bit in the tty_port::iflags field. Introduce helpers
tty_port_set_initialized() and tty_port_initialized() to abstract
atomic bit ops.

Note: the transforms for test_and_set_bit() and test_and_clear_bit()
are unnecessary as the state transitions are already mutually exclusive;
the tty lock prevents concurrent open/close/hangup.

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-30 09:26:55 -07:00
Peter Hurley 80f02d5424 tty: Replace ASYNC_SUSPENDED bit and update atomically
Replace ASYNC_SUSPENDED bit in the tty_port::flags field with
TTY_PORT_SUSPENDED bit in the tty_port::iflags field. Introduce helpers
tty_port_set_suspended() and tty_port_suspended() to abstract
atomic bit ops.

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-30 09:26:55 -07:00
Peter Hurley 807c8d81f4 tty: Replace ASYNC_NORMAL_ACTIVE bit and update atomically
Replace ASYNC_NORMAL_ACTIVE bit in the tty_port::flags field with
TTY_PORT_ACTIVE bit in the tty_port::iflags field. Introduce helpers
tty_port_set_active() and tty_port_active() to abstract atomic bit ops.

Extract state changes from port lock sections, as this usage is
broken and confused; the state transitions are protected by the
tty lock (which mutually excludes parallel open/close/hangup),
and no user tests the active state while holding the port lock.

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-30 09:26:55 -07:00