Re: [SMP lock BUG?] Re: Feedback on preemptible kernel patch

Manfred Spraul (
Sun, 9 Sep 2001 09:38:16 +0200

This is a multi-part message in MIME format.

Content-Type: text/plain;
Content-Transfer-Encoding: 7bit

> #define kmap_atomic(page,idx) ctx_sw_off(); kmap(page);
> #define kunmap_atomic(page,idx) ctx_sw_on(); kunmap(page);
No. kmap_atomic is called from interrupt context, and kmap calls

I thought about the attached patch (completely untested).


------=_NextPart_000_0013_01C13913.2720D6F0 Content-Type: application/octet-stream; name="patch-untested" Content-Transfer-Encoding: quoted-printable Content-Disposition: attachment; filename="patch-untested"

--- highmem.h.prev Sun Sep 9 08:59:04 2001=0A= +++ highmem.h Sun Sep 9 09:00:07 2001=0A= @@ -88,6 +88,7 @@=0A= if (page < highmem_start_page)=0A= return page_address(page);=0A= =0A= + ctx_sw_off();=0A= idx =3D type + KM_TYPE_NR*smp_processor_id();=0A= vaddr =3D __fix_to_virt(FIX_KMAP_BEGIN + idx);=0A= #if HIGHMEM_DEBUG=0A= @@ -119,6 +120,7 @@=0A= pte_clear(kmap_pte-idx);=0A= __flush_tlb_one(vaddr);=0A= #endif=0A= + ctx_sw_on();=0A= }=0A= =0A= #endif /* __KERNEL__ */=0A=


- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to More majordomo info at Please read the FAQ at