Changes in Kconfig

bacc15e0 - hid: bpf: add BPF_JIT dependency

Fri, 19 Jul 2024 09:51:07 +0000

hid: bpf: add BPF_JIT dependencyThe module does not do anything when the JIT is disabled, but insteadcauses a warning:In file included from include/linux/bpf_verifier.h:7, from drivers/hid/bpf/hid_bpf_struct_ops.c:10:drivers/hid/bpf/hid_bpf_struct_ops.c: In function 'hid_bpf_struct_ops_init':include/linux/bpf.h:1853:50: error: statement with no effect [-Werror=unused-value] 1853 | #define register_bpf_struct_ops(st_ops, type) ({ (void *)(st_ops); 0; }) | ^~~~~~~~~~~~~~~~drivers/hid/bpf/hid_bpf_struct_ops.c:305:16: note: in expansion of macro 'register_bpf_struct_ops' 305 | return register_bpf_struct_ops(&bpf_hid_bpf_ops, hid_bpf_ops); | ^~~~~~~~~~~~~~~~~~~~~~~Add a Kconfig dependency to only allow building the HID-BPF supportwhen a JIT is enabled.Fixes: ebc0d8093e8c ("HID: bpf: implement HID-BPF through bpf_struct_ops")Signed-off-by: Arnd Bergmann Link: https://patch.msgid.link/96a00b6f-eb81-4c67-8c4b-6b1f3f045034@app.fastmail.comSigned-off-by: Benjamin Tissoires List of files: /linux-6.15/drivers/hid/bpf/Kconfig

4e0b1b07 - HID: bpf: enforce HID_BPF dependencies

Tue, 06 Dec 2022 14:59:34 +0000

HID: bpf: enforce HID_BPF dependenciesAs mentioned in the link below, having JIT and BPF is not enough tohave fentry/fexit/fmod_ret APIs. This resolves the error thathappens on a system without tracing enabled when hid-bpf tries toload itself.Link: https://lore.kernel.org/r/CABRcYmKyRchQhabi1Vd9RcMQFCcb=EtWyEbFDFRTc-L-U8WhgA@mail.gmail.comFixes: f5c27da4e3c8 ("HID: initial BPF implementation")Signed-off-by: Benjamin Tissoires Reviewed-by: Florent Revest Reviewed-by: Jiri Kosina Link: https://lore.kernel.org/r/20221206145936.922196-4-benjamin.tissoires@redhat.com List of files: /linux-6.15/drivers/hid/bpf/Kconfig

f5c27da4 - HID: initial BPF implementation

Thu, 03 Nov 2022 15:57:44 +0000

HID: initial BPF implementationDeclare an entry point that can use fmod_ret BPF programs, andalso an API to access and change the incoming data.A simpler implementation would consist in just callinghid_bpf_device_event() for any incoming event and let users dealwith the fact that they will be called for any event of any device.The goal of HID-BPF is to partially replace drivers, so this situationcan be problematic because we might have programs which will step oneach other toes.For that, we add a new API hid_bpf_attach_prog() that can be calledfrom a syscall and we manually deal with a jump table in hid-bpf.Whenever we add a program to the jump table (in other words, when weattach a program to a HID device), we keep the number of time we addedthis program in the jump table so we can release it whenever there areno other users.HID devices have an RCU protected list of available programs in thejump table, and those programs are called one after the other thanksto bpf_tail_call().To achieve the detection of users losing their fds on the programs weattached, we add 2 tracing facilities on bpf_prog_release() (for whena fd is closed) and bpf_free_inode() (for when a pinned program getsunpinned).Reviewed-by: Greg Kroah-Hartman Signed-off-by: Benjamin Tissoires Signed-off-by: Jiri Kosina List of files: /linux-6.15/drivers/hid/bpf/Kconfig