return hidden bug
    Signed-off-by: Roel Kluin <12o3l@tiscali.nl>
diff --git a/arch/alpha/kernel/pci_iommu.c b/arch/alpha/kernel/pci_iommu.c

index e1c4707..6a69425 100644

--- a/arch/alpha/kernel/pci_iommu.c

+++ b/arch/alpha/kernel/pci_iommu.c

@@ -365,8 +365,8 @@ pci_unmap_single(struct pci_dev *pdev, dma_addr_t dma_addr, size_t size,

 		printk(KERN_ERR "Bogus pci_unmap_single: dma_addr %lx "

 		       " base %lx size %x\n", dma_addr, arena->dma_base,

 		       arena->size);

-		return;

 		BUG();

+		return;

 	}
 	npages = calc_npages((dma_addr & ~PAGE_MASK) + size);

-

On Mon, 22 Oct 2007 03:05:05 +0200
BUG() will terminate the process that runs into it, so you can

just remove the return alltogether.  If BUG() is hit, the return

will never be reached.
--

"Debugging is twice as hard as writing the code in the first place.

Therefore, if you write the code as cleverly as possible, you are,

by definition, not smart enough to debug it." - Brian W. Kernighan

-

Looking at the printk, I don't think this particular error ought to

forcefully kill things.
--

Mathematics is the supreme nostalgia of our time.

-

True, but obviously not intended. I think the intention was to expose this bug.
-

Arguing intentions is very dangerous. I've written code like that

where the intention is to make it simple to turn a printk into a full

bug and back and forth during development. At the end of the day, the

fact remains that you're changing behavior.
Let me turn this around. Do you have an alpha and have you tried out

your patch? If not, then I'd suggest turning it into a WARN_ON(1)

instead, as in this specific case you're risking turning what was a

working system into one that doesn't.

-

No, I haven't and, I will change it, but it's included with my other

changes. see the reply that I'll write shortly for.

[PATCH retry] return hidden bug and unlock bugs.
Roel
-

Hugely trust inspiring isn't it -- the amount of eyes and comments you'll

get even on trivial patches like this? This development model is working!
Now if only we'd sometimes get some for non trivial patches as well...
Rene.

-

Go easy with the snarkiness, hmm? It's the trivial ones that seem to

be the most dangerous. The larger ones actually get *tested*
That's certainly true regardless, but for myself, I'd rather throw

some reviews out for the small ones since I have adequate time and

knowledge for them. The larger ones require domain specific knowledge

I lack, and time I don't have.
~r.

-

I was also commenting and don't generally on anything much more involved so 
Exactly the problem. Comment was mostly triggered due to me looking at a

problem with a proprietary CD-ROM driver again tonight that I posted a few

months ago where the only comment has been from the fellow author. There the

problem was the block layer blowing up and given that it seems unlikely that

this wouldn't be a problem inside the newbie-driver itself, that the block

part of it was actually really small and people said they'd look at it, the

subsequent thundering silence still annoys me.
Ofcourse, now it seems the kernel itself has moved on enough that the driver

doesn't work at _all_ anymore and I at the moment lack the time to spend the

required hours googling around trying to find out what the heck changed out

from under me so that I might get it to at least do what it already did do.
Hey, I don't actually know and maybe I'm just wrong but I have the feeling

that over the last 1 or 2 years most new developers seem to be either people

that are payed to be so, perhaps in the form of graduation, or janitors. The

kernel is much, much more complex than even only a few years ago and at the

same time the number of knowledgeable developers who'll do something other

than their own thing and otherwise just wait around for something perfect to

merge seems to be approaching zero.
That is -- I do not feel that the current developer base is expending overly

many efforts to appear welcoming.
Please feel free to do the open-source thing and argue that's actually an

advantage (there we have that snarkiness again...) or otherwise ignore me.

I'll just sit here and be grumpy anyway. Might be better after a good

night's sleep...
Rene.
-

Hi,
This isn't true when CONFIG_BUG is disabled (in embedded builds, for example).
                                    Pekka

-

On Mon, 22 Oct 2007 12:30:00 +0300
*blink*
I guess people who disable CONFIG_BUG really choose to shoot themselves

in the foot when something bad happens.  The kernel is full of error

paths where the current thread really should not be continuing.
Oh well...
--

"Debugging is twice as hard as writing the code in the first place.

Therefore, if you write the code as cleverly as possible, you are,

by definition, not smart enough to debug it." - Brian W. Kernighan

-

Hi Rik,
Sure, if you disable BUG_ON, it may or may not work. But making it

*worse* on purpose seems pointless.

-

This is true in general.  However, if someone builds the kernel

with CONFIG_BUG disabled then the return statement will make a

difference.  Of course, if you're brave enough to have CONFIG_BUG

off then you can deal with the fall-out :)
Cheers,

--

Visit Openswan at http://www.openswan.org/

Email: Herbert Xu ~{PmV>HI~} <herbert@gondor.apana.org.au>

Home Page: http://gondor.apana.org.au/~herbert/

PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt

-

---

    hidden bug returns
    Signed-off-by: Roel Kluin <12o3l@tiscali.nl>

---

diff --git a/arch/alpha/kernel/pci_iommu.c b/arch/alpha/kernel/pci_iommu.c

index e1c4707..ca55c33 100644

--- a/arch/alpha/kernel/pci_iommu.c

+++ b/arch/alpha/kernel/pci_iommu.c

@@ -365,7 +365,6 @@ pci_unmap_single(struct pci_dev *pdev, dma_addr_t dma_addr, size_t size,

 		printk(KERN_ERR "Bogus pci_unmap_single: dma_addr %lx "

 		       " base %lx size %x\n", dma_addr, arena->dma_base,

 		       arena->size);

-		return;

 		BUG();

 	}
-

On Mon, 22 Oct 2007 03:53:30 +0200
Acked-by: Rik van Riel <riel@redhat.com>
--

"Debugging is twice as hard as writing the code in the first place.

Therefore, if you write the code as cleverly as possible, you are,

by definition, not smart enough to debug it." - Brian W. Kernighan

-