I allocate memory by ExAllocatePoolWithTag in a driver for WinXP. When I try
to free memory with ExFreePoolWithTag, there appears BSOD. Crash dump
analysis shows that

Arg1: 00000012, caller is trying to free nonpaged pool at an IRQL above
DISPATCH_LEVEL
Arg2: 00000008, current IRQL

Then, how I should free allocated memory?

ExFreePool cannot be called from the ISR or KeSynchronizeExecution callback
or under interrupt spin lock.

--
Maxim Shatskih, Windows DDK MVP
StorageCraft Corporation
maxim@storagecraft.com
http://www.storagecraft.com

"Kid of the neon" <Kid of the neon@discussions.microsoft.com> wrote in message
news:2F2E1562-C28F-42AD-A8A4-106188294F58@microsoft.com...

You cannot allocate or free memory at device IRPQ. You need to change your
logic to release the memory once the IRQL is down to DISPATCH_LEVEL or
lower.

While I do not know your code, the error below is typically caused by trying
to free the memory in the interrupt service routine once the transfer to the
device is complete. If so defer the freeing of the memory to the time you
complete the IRP in the DPC routine.


--
Don Burn (MVP, Windows DDK)
Windows 2k/XP/2k3 Filesystem and Driver Consulting
Website: http://www.windrvr.com
Blog: http://msmvps.com/blogs/WinDrvr
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"Kid of the neon" <Kid of the neon@discussions.microsoft.com> wrote in
message news:2F2E1562-C28F-42AD-A8A4-106188294F58@microsoft.com...

I hope you do have a DPC scheduled out of the ISR.

Is the free call made in the ISR? Or in a routine at high IRQL?
--
--GNR


"Don Burn" wrote: