2018-04-10 16:06 GMT+09:00 Krzysztof Kozlowski <krzk@xxxxxxxxxx>: > On Sun, Apr 8, 2018 at 8:07 PM, Paweł Chmiel > <pawel.mikolaj.chmiel@xxxxxxxxx> wrote: >> All banks with GPIO interrupts should be at beginning >> of bank array and without any other types of banks between them. >> This order is expected by exynos_eint_gpio_irq, when doing >> interrupt group to bank translation. >> Otherwise, kernel NULL pointer dereference would happen >> when trying to handle interrupt, due to wrong bank being looked up. >> Observed on s5pv210, when trying to handle gpj0 interrupt, >> where kernel was mapping it to gpi bank. > > Thanks for the patch. The issue looks real although one thing was > missed - there is a gap in SVC group between GPK2 and GPL0 (pointed by > Marek Szyprowski): > > 0x0 - EINT_23 - gpk0 > 0x1 - EINT_24 - gpk1 > 0x2 - EINT_25 - gpk2 > 0x4 - EINT_27 - gpl0 > 0x7 - EINT_8 - gpm0 > > Maybe this should be done differently - to remove such hidden > requirement entirely in favor of another parameter of > EXYNOS_PIN_BANK_EINTG argument? Perhaps let's limit this patch to s5pv210 and Exynos5410 alone, where a simple swap of bank order in the arrays should be okay. We might also need to have some fixes on 4x12, because I noticed that in exynos4x12_pin_banks0[] there is a hole in eint_offsets between gpd1 and gpf0 and exynos4x12_pin_banks1[] starts with gpk0 that has eint_offset equal to 0x08 (not 0). > Anyway if such hidden requirement > stays, then please document it in the source code (it maybe next to > PIN order... or next macro... or also in exynos_eint_gpio_irq()). > > Beside that please add cc-stable and appropriate fixes tag, Agreed. Probably the only safe way of documenting this is to put it inside each bank array, so that when someone creates a copy/paste for new SoC, the comment is clearly visible... Perhaps something like: /* Must start with EINTG banks, ordered by EINT group number. */ Best regards, Tomasz -- To unsubscribe from this list: send the line "unsubscribe linux-gpio" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html