| Message ID | 20240829102007.34355-1-amit@kernel.org |
|---|---|
| State | New |
| Headers | show |
| Series | crypto: ccp: do not request interrupt on cmd completion when irqs disabled | expand |
On Thu, Aug 29, 2024 at 12:20:07PM +0200, Amit Shah wrote: > From: Amit Shah <amit.shah@amd.com> > > While sending a command to the PSP, we always requested an interrupt > from the PSP after command completion. This worked for most cases. For > the special case of irqs being disabled -- e.g. when running within > crashdump or kexec contexts, we should not set the SEV_CMDRESP_IOC flag, > so the PSP knows to not attempt interrupt delivery. > > Fixes: 8ef979584ea8 ("crypto: ccp: Add panic notifier for SEV/SNP firmware shutdown on kdump") > > Based-on-patch-by: Tom Lendacky <thomas.lendacky@amd.com> > Signed-off-by: Amit Shah <amit.shah@amd.com> > --- > drivers/crypto/ccp/sev-dev.c | 13 ++++++++++++- > 1 file changed, 12 insertions(+), 1 deletion(-) Patch applied. Thanks.
diff --git a/drivers/crypto/ccp/sev-dev.c b/drivers/crypto/ccp/sev-dev.c index 9810edbb272d..1775bac7f597 100644 --- a/drivers/crypto/ccp/sev-dev.c +++ b/drivers/crypto/ccp/sev-dev.c @@ -910,7 +910,18 @@ static int __sev_do_cmd_locked(int cmd, void *data, int *psp_ret) sev->int_rcvd = 0; - reg = FIELD_PREP(SEV_CMDRESP_CMD, cmd) | SEV_CMDRESP_IOC; + reg = FIELD_PREP(SEV_CMDRESP_CMD, cmd); + + /* + * If invoked during panic handling, local interrupts are disabled so + * the PSP command completion interrupt can't be used. + * sev_wait_cmd_ioc() already checks for interrupts disabled and + * polls for PSP command completion. Ensure we do not request an + * interrupt from the PSP if irqs disabled. + */ + if (!irqs_disabled()) + reg |= SEV_CMDRESP_IOC; + iowrite32(reg, sev->io_regs + sev->vdata->cmdresp_reg); /* wait for command completion */