4.19-stable review patch. If anyone has any objections, please let me know.
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From: Finn Thain fthain@telegraphics.com.au
[ Upstream commit 5f93d7081a47e1972031ccf57c4b2779eee162fb ]
The BUG_ON assertions I added to the via-macii driver over a decade ago haven't fired AFAIK. Some can never fire (by inspection). One assertion checks for a NULL pointer, but that would merely substitute a BUG crash for an Oops crash. Remove the pointless BUG_ON assertions and replace the others with a WARN_ON and an array bounds check.
Tested-by: Stan Johnson userm57@yahoo.com Signed-off-by: Finn Thain fthain@telegraphics.com.au Signed-off-by: Michael Ellerman mpe@ellerman.id.au Stable-dep-of: d301a71c76ee ("macintosh/via-macii: Fix "BUG: sleeping function called from invalid context"") Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/macintosh/via-macii.c | 49 +++++------------------------------ 1 file changed, 7 insertions(+), 42 deletions(-)
diff --git a/drivers/macintosh/via-macii.c b/drivers/macintosh/via-macii.c index cf6f7d52d6bee..fc6ad5bf1875a 100644 --- a/drivers/macintosh/via-macii.c +++ b/drivers/macintosh/via-macii.c @@ -120,23 +120,6 @@ static int srq_asserted; /* have to poll for the device that asserted it */ static int command_byte; /* the most recent command byte transmitted */ static int autopoll_devs; /* bits set are device addresses to be polled */
-/* Sanity check for request queue. Doesn't check for cycles. */ -static int request_is_queued(struct adb_request *req) { - struct adb_request *cur; - unsigned long flags; - local_irq_save(flags); - cur = current_req; - while (cur) { - if (cur == req) { - local_irq_restore(flags); - return 1; - } - cur = cur->next; - } - local_irq_restore(flags); - return 0; -} - /* Check for MacII style ADB */ static int macii_probe(void) { @@ -213,8 +196,6 @@ static void macii_queue_poll(void) else next_device = ffs(autopoll_devs) - 1;
- BUG_ON(request_is_queued(&req)); - adb_request(&req, NULL, ADBREQ_NOSEND, 1, ADB_READREG(next_device, 0));
@@ -237,18 +218,13 @@ static int macii_send_request(struct adb_request *req, int sync) int err; unsigned long flags;
- BUG_ON(request_is_queued(req)); - local_irq_save(flags); err = macii_write(req); local_irq_restore(flags);
- if (!err && sync) { - while (!req->complete) { + if (!err && sync) + while (!req->complete) macii_poll(); - } - BUG_ON(request_is_queued(req)); - }
return err; } @@ -327,9 +303,6 @@ static int macii_reset_bus(void) { static struct adb_request req; - if (request_is_queued(&req)) - return 0; - /* Command = 0, Address = ignored */ adb_request(&req, NULL, 0, 1, ADB_BUSRESET);
@@ -346,10 +319,6 @@ static void macii_start(void)
req = current_req;
- BUG_ON(req == NULL); - - BUG_ON(macii_state != idle); - /* Now send it. Be careful though, that first byte of the request * is actually ADB_PACKET; the real data begins at index 1! * And req->nbytes is the number of bytes of real data plus one. @@ -387,7 +356,6 @@ static void macii_start(void) static irqreturn_t macii_interrupt(int irq, void *arg) { int x; - static int entered; struct adb_request *req;
if (!arg) { @@ -398,8 +366,6 @@ static irqreturn_t macii_interrupt(int irq, void *arg) return IRQ_NONE; }
- BUG_ON(entered++); - last_status = status; status = via[B] & (ST_MASK|CTLR_IRQ);
@@ -408,7 +374,7 @@ static irqreturn_t macii_interrupt(int irq, void *arg) if (reading_reply) { reply_ptr = current_req->reply; } else { - BUG_ON(current_req != NULL); + WARN_ON(current_req); reply_ptr = reply_buf; }
@@ -473,8 +439,8 @@ static irqreturn_t macii_interrupt(int irq, void *arg)
case reading: x = via[SR]; - BUG_ON((status & ST_MASK) == ST_CMD || - (status & ST_MASK) == ST_IDLE); + WARN_ON((status & ST_MASK) == ST_CMD || + (status & ST_MASK) == ST_IDLE);
/* Bus timeout with SRQ sequence: * data is "XX FF" while CTLR_IRQ is "L L" @@ -501,8 +467,8 @@ static irqreturn_t macii_interrupt(int irq, void *arg) } }
- if (macii_state == reading) { - BUG_ON(reply_len > 15); + if (macii_state == reading && + reply_len < ARRAY_SIZE(reply_buf)) { reply_ptr++; *reply_ptr = x; reply_len++; @@ -545,6 +511,5 @@ static irqreturn_t macii_interrupt(int irq, void *arg) break; }
- entered--; return IRQ_HANDLED; }