Re: [PATCH] nvme-tcp: Fix implicit padding in struct nvme_tcp_term_pdu

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



The nvme_tcp_term_pdu definition needs to be updated anyways to match
the spec. FEI is at offset 10, so it isn't 4-byte-aligned. I think we
have gotten away with this so far because the NVMe/TCP driver never
sends H2CTermReq and doesn't interpret C2HTermReq.
Mirroring numdl/numdu in nvme_get_log_page_command, the definition
should look something like:
struct nvme_tcp_term_pdu {
        struct nvme_tcp_hdr hdr;
        __le16 fes;
        __le16 feil;
        __le16 feiu;
        __u8 rsvd[10];
};

Best,
Caleb

On Mon, Mar 20, 2023 at 4:29 AM Geert Uytterhoeven <geert@xxxxxxxxxxxxxx> wrote:

On m68k:

    drivers/nvme/host/tcp.c: In function ‘nvme_tcp_init_module’:
    include/linux/compiler_types.h:397:38: error: call to ‘__compiletime_assert_723’ declared with attribute error: BUILD_BUG_ON failed: sizeof(struct nvme_tcp_term_pdu) != 24

Indeed, on m68k the minimum alignment is 2 bytes, not 4 bytes, thus
triggering the check added in commit 7e87965d3807ab1f ("nvme-tcp: add
nvme-tcp pdu size build protection"), and indicating that NVMe over
Fabrics TCP on m68k must be incompatible with other platforms.

Fix this by adding explicit padding.

Fixes: fc221d05447aa6db ("nvme-tcp: Add protocol header")
Signed-off-by: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx>
---
 include/linux/nvme-tcp.h | 1 +
 1 file changed, 1 insertion(+)

diff --git a/include/linux/nvme-tcp.h b/include/linux/nvme-tcp.h
index 75470159a194d97f..ba8f82672e39730f 100644
--- a/include/linux/nvme-tcp.h
+++ b/include/linux/nvme-tcp.h
@@ -115,6 +115,7 @@ struct nvme_tcp_icresp_pdu {
 struct nvme_tcp_term_pdu {
        struct nvme_tcp_hdr     hdr;
        __le16                  fes;
+       __u8                    rsvd2[2];
        __le32                  fei;
        __u8                    rsvd[8];
 };
--
2.34.1






[Index of Archives]     [Video for Linux]     [Yosemite News]     [Linux S/390]     [Linux Kernel]     [Linux SCSI]

  Powered by Linux