Commit 42ab37ea authored by Keith Busch's avatar Keith Busch
Browse files

nvme: module parameter to disable pi with offsets 



A recent commit enables integrity checks for formats the previous kernel
versions registered with the "nop" integrity profile. This means
namespaces using that format become unreadable when upgrading the kernel
past that commit.

Introduce a module parameter to restore the "nop" integrity profile so
that storage can be readable once again. This could be a boot device, so
the setting needs to happen at module load time.

Fixes: 921e81db ("nvme: allow integrity when PI is not in first bytes")
Reported-by: default avatarDavid Wei <dw@davidwei.uk>
Reviewed-by: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarKanchan Joshi <joshi.k@samsung.com>
Reviewed-by: default avatarChaitanya Kulkarni <kch@nvidia.com>
Signed-off-by: default avatarKeith Busch <kbusch@kernel.org>
parent f54f0d0e

drivers/nvme/host/core.c

+17 −2
Original line number Diff line number Diff line
@@ -91,6 +91,17 @@ module_param(apst_secondary_latency_tol_us, ulong, 0644); 
MODULE_PARM_DESC(apst_secondary_latency_tol_us,

	"secondary APST latency tolerance in us");



/*

 * Older kernels didn't enable protection information if it was at an offset.

 * Newer kernels do, so it breaks reads on the upgrade if such formats were

 * used in prior kernels since the metadata written did not contain a valid

 * checksum.

 */

static bool disable_pi_offsets = false;

module_param(disable_pi_offsets, bool, 0444);

MODULE_PARM_DESC(disable_pi_offsets,

	"disable protection information if it has an offset");



/*

 * nvme_wq - hosts nvme related works that are not reset or delete

 * nvme_reset_wq - hosts nvme reset works
@@ -1926,8 +1937,12 @@ static void nvme_configure_metadata(struct nvme_ctrl *ctrl, 


	if (head->pi_size && head->ms >= head->pi_size)

		head->pi_type = id->dps & NVME_NS_DPS_PI_MASK;

	if (!(id->dps & NVME_NS_DPS_PI_FIRST))

	if (!(id->dps & NVME_NS_DPS_PI_FIRST)) {

		if (disable_pi_offsets)

			head->pi_type = 0;

		else

			info->pi_offset = head->ms - head->pi_size;

	}



	if (ctrl->ops->flags & NVME_F_FABRICS) {

		/*